In a one-way ANOVA test with four groups, the null hypothesis states that there is no significant difference between the means of all four groups.
This means that any observed differences in the sample means are due to chance or random integral alone and not because of any systematic or real differences between the groups.
The null hypothesis assumes that the population means for each group are equal, which implies that there is no effect or influence of the independent variable on the dependent variable. If the null hypothesis is accepted, it means that any observed differences between the groups are not statistically significant and do not support the alternative hypothesis.
To determine whether to accept or reject the null hypothesis, researchers calculate the F-statistic, which compares the variability between the sample means to the variability within each group. If the calculated F-value is greater than the critical F-value for a given level of significance, the null hypothesis is rejected in favor of the alternative hypothesis, indicating that there is a significant difference between at least two of the group means.
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Evaluate the requested derivatives: a) g(x) = 3x^3 -8x^2 -2x + 35 Find g'(2). b) k(x) = 1 /x^5 Find k"(1) c) n(x) = (-4x + 2)(3x^2 - 5x + 2) Find n'(0)
a) The derivative of g(x) at x=2 is g'(2) = 2.
b) The second derivative of k(x) at x=1 is k"(1) = -30.
c) The derivative of n(x) at x=0 is n'(0) = -18.
a) To find g'(x), we need to take the derivative of g(x) with respect to x. Let's differentiate each term separately:
g(x) = 3x³ - 8x² - 2x + 35
The derivative of 3x³ is obtained by applying the power rule, which states that if we have a term of the form [tex]ax^n[/tex], the derivative is given by [tex]nax^{(n-1)[/tex]. In this case, the derivative of 3x³ is 3 * 3x², which simplifies to 9x².
The derivative of -8x² is obtained in a similar manner, resulting in -16x.
The derivative of -2x is -2.
Since 35 is a constant term, its derivative is zero.
Now, let's combine these derivatives to find g'(x):
g'(x) = 9x² - 16x - 2
To find g'(2), we substitute x = 2 into the derivative:
g'(2) = 9(2)² - 16(2) - 2
= 9(4) - 32 - 2
= 36 - 32 - 2
= 2
Therefore, g'(2) = 2.
b) To find k"(x), we need to take the second derivative of k(x) with respect to x. Let's differentiate each term:
k(x) = 1 / [tex]x^5[/tex]
The derivative of 1/[tex]x^5[/tex] can be found using the power rule and the chain rule. The power rule states that the derivative of [tex]x^n[/tex] is n[tex]x^{(n-1)[/tex], and the chain rule applies when we have a function within another function. In this case, the derivative of 1/[tex]x^5[/tex] is -5/[tex]x^6[/tex].
Taking the derivative of -5/[tex]x^6[/tex], we apply the power rule again, resulting in 30/[tex]x^7[/tex].
Now, let's find k"(x) by differentiating -5/[tex]x^6[/tex] again:
k"(x) = -30/[tex]x^7[/tex]
To find k"(1), we substitute x = 1 into the second derivative:
k"(1) = -30/([tex]1^7[/tex])
= -30/1
= -30
Therefore, k"(1) = -30.
c) To find n'(x), we need to take the derivative of n(x) with respect to x. We can apply the product rule to differentiate the two factors of n(x):
n(x) = (-4x + 2)(3x² - 5x + 2)
Using the product rule, the derivative of n(x) is given by:
n'(x) = (-4x + 2)(d/dx)(3x² - 5x + 2) + (3x² - 5x + 2)(d/dx)(-4x + 2)
To differentiate each term, we use the power rule:
(d/dx)(3x² - 5x + 2) = 6x - 5
(d/dx)(-4x + 2) = -4
Substituting these derivatives back into n'(x), we get:
n'(x) = (-4x + 2)(6x - 5) + (3x² - 5x + 2)(-4)
Now, let's find n'(0) by substituting x = 0 into the derivative:
n'(0) = (-4(0) + 2)(6(0) - 5) + (3(0)² - 5(0) + 2)(-4)
= (2)(0 - 5) + (0 - 0 + 2)(-4)
= (2)(-5) + (2)(-4)
= -10 - 8
= -18
Therefore, n'(0) = -18.
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Plz answer quickly will you brainlist
Answer:
Positive association is correct
Step-by-step explanation: The dots form are going up, forming a positive line. If they were to go down they would be negative. So in this case positive association is correct
Consider the rectangular prism.What is the surface area of the rectangular prism?
124 in
208 in
240 in
248 in
Answer: 240 in 2
Step-by-step explanation:
just did it
I NEEDDD HELP PLEASE!!! this is due today!
Answer:
What is it love ?
Step-by-step explanation:
Find the value of x. 2 3 6
Elena cashed a check for $$4350 at Quick Cash. The fee to cash
a check is 12% of the amount of the check. How much did Elena
pay to cash her check?
Answer:
522
Step-by-step explanation:
Let A and B be two matrices of size 4 x 4 such that det(A)= 1. If B is a singular matrix then det(3A^-2 B^T) +1 =
0
1
None of the mentioned
-1
2
The value of det(3A^-2B^T) + 1, given det(A) = 1 and B is a singular matrix, is :
1
To find the determinant of the given expression, let's break it down step by step.
Matrix A is 4x4 with det(A) = 1.
Matrix B is a singular matrix.
Find the inverse of matrix A.
Since A is given to be a 4x4 matrix with det(A) = 1, we know that A is invertible. Therefore, A^-1 exists.
Find the determinant of the expression 3A^-2B^T.
Let's calculate the determinant of 3A^-2B^T:
det(3A^-2B^T) = det(3) * det(A^-2) * det(B^T)
We know that det(A^-2) = (det(A))^(-2) = 1^(-2) = 1.
Also, det(B^T) = det(B) because the determinant of a transpose is the same as the determinant of the original matrix.
So, det(3A^-2B^T) = 3 * 1 * det(B) = 3 * det(B)
Determine the value of det(3A^-2B^T) + 1.
Since B is given to be a singular matrix, its determinant is 0.
Therefore, det(3A^-2B^T) + 1 = 3 * det(B) + 1 = 3 * 0 + 1 = 1.
So, the value of det(3A^-2B^T) + 1 is 1.
Therefore, the correct answer is 1.
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15 points!!! PLEASE HELP!!!
Find the solution to the following equations below and identify either one solution, no solution, or infinite solutions. Be able to explain your choice.
3(x+4)=3x+11
-2(x+3)=-2x-6
4(x-1) = 1/2(x-8)
3x-7=4+6 +4x
Answer:
3(x+4)=3x+11
3x + 12 = 3x + 11
3x + 1 = 3x
No solution
-2(x+3)=-2x-6
-2x - 6 = -2x - 6
x = x
Infinite solutions
4(x-1) = 1/2(x-8)
4x - 4 = 1/2x - 4
8x - 8 = x - 8
7x = 0
x = 0
One solution
3x-7=4+6 +4x
3x - 7 = 10 + 4x
x = -17
One solution
are 2x-1 +3x=0 and 5x-1=0 equivalent
Answer:
yes
Step-by-step explanation:
they both equal 5x=1 where x = 1/5
A researcher was interested in seeing if cats or dogs are more playful with their owners overall. The null hypothesis of this study is
a. dogs will play with their owners more than cats
b. cats will play with their owners more than dogs
c. cats and dogs play with their owners at the same rate
d. more information is needed
The null hypothesis of this study is the statement that there is no significant difference between the playfulness of cats and dogs with their owners. In other words, the researcher assumes that both cats and dogs will play with their owners at the same rate. This is option c.
To test this hypothesis, the researcher would need to collect data on the playfulness of both cats and dogs with their owners. This could involve observing the animals during playtime or asking owners to self-report how often their pets play with them. The data would then be analyzed using statistical tests to determine if there is a significant difference in the average rates of playfulness between cats and dogs.
It is important to note that the null hypothesis does not necessarily reflect the researcher's personal beliefs or assumptions about the topic. Instead, it serves as a baseline assumption that can be tested through empirical research. If the data collected suggests that cats and dogs do not play with their owners at the same rate, then the null hypothesis would be rejected, and the researcher would need to explore alternative explanations for the observed differences.
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Question 3 [20 marks] Consider two utility functions u(x) and ˜u(x) where x is the amount of money consumed by the agent.
a) Explain formally what it means that an agent with utility function u is more risk averse than an agent with utility function ˜u.
b) Show that an agent with utility function u(x) = log x is more risk averse than an agent with utility function ˜u(x) = √ x.
a) Formal explanation of risk aversion An agent with utility function u is more risk averse than an agent with utility function ˜u if the former has a higher marginal utility of consumption and a diminishing marginal utility of consumption.
The marginal utility of consumption is defined as the amount of utility gained from an additional unit of consumption.
b) Show that an agent with utility function u(x) = log x is more risk averse than an agent with utility function ˜u(x) = √ x. An agent with utility function u(x) = log x is more risk averse than an agent with utility function ˜u(x) = √ x. To show this, we need to find the Arrow-Pratt coefficient of risk aversion, also known as the coefficient of relative risk aversion. The Arrow-Pratt coefficient of risk aversion is given by :-u''(x)/u'(x)Where u'(x) is the first derivative of u with respect to x and u''(x) is the second derivative of u with respect to x.
The Arrow-Pratt coefficient of risk aversion measures the curvature of the utility function. A higher value of the Arrow-Pratt coefficient of risk aversion indicates greater risk aversion. Let us calculate the Arrow-Pratt coefficient of risk aversion for both functions:-For u(x) = log x, u'(x) = 1/x, and u''(x) = -1/x². Therefore, the Arrow-Pratt coefficient of risk aversion for u(x) is given by:-u''(x)/u'(x) = -1/x² ÷ (1/x) = -x For ˜u(x) = √ x, ˜u'(x) = 1/2√ x, and ˜u''(x) = -1/4x^(3/2). Therefore, the Arrow-Pratt coefficient of risk aversion for ˜u(x) is given by:-˜u''(x)/˜u'(x) = -1/4x^(3/2) ÷ (1/2√ x) = -1/2√ x
Therefore, since -x < -1/2√ x, the agent with the utility function u(x) = log x is more risk averse than the agent with the utility function ˜u(x) = √ x.
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A random variable has a normal distribution with mean 7.5 and standard deviation 2.5. For which of the following is the probability equal to 0?
a) Less than 5.0
b) Between 4.0 and 10.0
c) Greater than 9.0
d) Between 6.0 and 8.0
The probability is equal to 0 for the option "a) Less than 5.0."Explanation:Given, the mean of the normal distribution, μ = 7.5 and the standard deviation of the normal distribution, σ = 2.5 The formula to find the Z-score, z is given by;z = (x - μ)/σwhere x is the value of the random variable under consideration.
a) To find the probability of the random variable being less than 5, we find the Z-score;z = (5 - 7.5)/2.5 = -1 Therefore, P(X < 5) = P(Z < -1)Using the standard normal table, the probability corresponding to the Z-score -1 is 0.1587.Therefore, the probability of the random variable being less than 5 is 0.1587.
b) To find the probability of the random variable being between 4.0 and 10.0, we find the Z-score corresponding to each value and calculate the difference in their probability. The probability required will be the absolute value of this difference. z 1 = (4 - 7.5)/2.5 = -1.4 z 2 = (10 - 7.5)/2.5 = 1 Therefore, P(4 < X < 10) = P(-1.4 < Z < 1) = P(Z < 1) - P(Z < -1.4) = 0.8413 - 0.0808 = 0.7605
c ).To find the probability of the random variable being greater than 9.0, we find the Z-score;z = (9 - 7.5)/2.5 = 0.6 Therefore, P(X > 9) = P(Z > 0.6)Using the standard normal table, the probability corresponding to the Z-score 0.6 is 0.2743.Therefore, the probability of the random variable being greater than 9.0 is 0.2743
d) To find the probability of the random variable being between 6.0 and 8.0, we find the Z-score corresponding to each value and calculate the difference in their probability. The probability required will be the absolute value of this difference. z 1 = (6 - 7.5)/2.5 = -0.6z2 = (8 - 7.5)/2.5 = 0.2Therefore, P(6 < X < 8) = P(-0.6 < Z < 0.2) = P(Z < 0.2) - P(Z < -0.6) = 0.5793 - 0.2743 = 0.305Therefore, the probability is equal to 0 for the option "a) Less than 5.0."
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A random variable has a normal distribution with mean 7.5 and standard deviation 2.5. The following is the probability equal to 0.
Option a) Less than 5.0 is correct.
Note that the normal distribution is symmetrical. So, the probabilities of events occurring are equal on either side of the mean.
The probability is zero when the range of events is beyond the limits of the standard normal distribution, which is from -3 to +3. Now let's standardize the values below:
a. less than 5.0: The formula to standardize is
[tex]z = (x - \mu) / \sigma[/tex]
z = (5 - 7.5) / 2.5
z = -1
Thus, the area of the left side of the standard normal distribution is zero, indicating that the probability of less than 5 is zero. Therefore, option a) is correct.
Other options are: b. Between 4.0 and 10.0: The probability that the values fall between 4 and 10 is 0.974 c. Greater than 9.0: The probability that the values are greater than 9 is 0.080 d. Between 6.0 and 8.0: The probability that the values fall between 6 and 8 is 0.329.
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For 2 + 5(x-3) > 3x + 11, the answer is x>
Answer:
x >12
Step-by-step explanation:
2 + 5(x-3) > 3x + 11
Distribute
2 + 5x - 15 > 3x+11
Combine like terms
5x -13 > 3x+11
Subtract 3x from each side
5x-13-3x> 3x+11-3x
2x-13 > 11
Add 13 to each side
3x-13+13> 11+13
2x> 24
Divide by 2
2x/2 > 24/2
x >12
What is the total weight of 3 bags if their individual weights are 2/5, 7/10 and 3/5 pound? Give your answer as a mixed number in siplest form
Answer:
1 7/10
Step-by-step explanation:
Given that:
Weight of bag 1 = 2/5 pounds
Weight of bag 2 = 7/10 pounds
Weight of bag 3 = 3/5 pounds
Total weight of the three bags :
2/5 + 7/10 + 3/5
Take the lcm of 5 and 10
Lcm of 5 and 10 = 10
(4 + 7 + 6) / 10
17 /10
= 1 7/10
A cylinder has a volume of 792 m and a radius of 6 m. Find its height.
Answer:
7 m
Step-by-step explanation:
you divide the volume by the radius I'm pretty sure. that's what I did and I got 7
Find the perimeter of the figure
Answer: 132ft
Step-by-step explanation:
9x4=36+36=72
30-9=21
21+21+9+9=60
60+72=132ft
What’s the answer???
Answer:
Question 7 = $2
Question 8 = $16
An article suggested that yield strength (ksi) for A36 grade steel is normally distributed with μ = 42 and σ = 5.0.
(a) What is the probability that yield strength is at most 39? Greater than 60? (Round your answers to four decimal places.)
at most 39 _________. greater than 60 _________. (b) What yield strength value separates the strongest 75% from the others? (Round your answer to three decimal places.)
_______ksi
A)The probability that the yield strength is greater than 60 is approximately 0.0003.
B)The yield strength value that separates the strongest 75% from the others is approximately 45.3725 ksi.
What is probability?
Probability is a fundamental concept in mathematics and statistics that quantifies the likelihood or chance of an event occurring. It provides a numerical measure of uncertainty or the relative frequency with which an event is expected to happen. In simpler terms, probability is a way of expressing how likely it is for a particular outcome or event to take place.
(a) The probability that yield strength is at most 39:
Using the standard normal distribution, we can calculate the z-score as follows:
[tex]\[ z = \frac{{39 - 42}}{{5.0}} = -0.6 \][/tex]
The cumulative probability associated with a z-score of -0.6 represents the probability of obtaining a value less than or equal to 39. Using a standard normal distribution table or a calculator, we find that this cumulative probability is approximately 0.2743.
Therefore, the probability that the yield strength is at most 39 is approximately 0.2743.
The probability that yield strength is greater than 60:
Converting 60 to a z-score:
[tex]\[ z = \frac{{60 - 42}}{{5.0}} = 3.6 \][/tex]
The cumulative probability associated with a z-score of 3.6 represents the probability of obtaining a value greater than 60. Using a standard normal distribution table or a calculator, we find that this cumulative probability is approximately 0.9997.
Since we want the probability of a value greater than 60, we subtract this cumulative probability from 1:
[tex]\[ P(\text{{yield strength}} > 60) = 1 - 0.9997 = 0.0003 \][/tex]
Therefore, the probability that the yield strength is greater than 60 is approximately 0.0003.
(b) The yield strength value that separates the strongest 75% from the others:
To find the yield strength value that separates the strongest 75% from the others, we need to find the z-score corresponding to the cumulative probability of 0.75. Using a standard normal distribution table or a calculator, we find that the z-score associated with a cumulative probability of 0.75 is approximately 0.6745.
Next, we can use the z-score formula to find the yield strength value:
[tex]\[ z = \frac{{x - \mu}}{{\sigma}} \][/tex]
Rearranging the formula to solve for x:
[tex]\[ x = \mu + (z \times \sigma) \][/tex]
Substituting the values into the formula:
[tex]\[ x = 42 + (0.6745 \times 5.0) = 45.3725 \][/tex]
Therefore, the yield strength value that separates the strongest 75% from the others is approximately 45.3725 ksi.
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The county recreation department cleared 3/4 of a mile for a trail in Washington Park. There will be a small sign every 1/12 mile along the trail. How many signs are needed?
Answer:
its 9 signs
Step-by-step explanation:
in order to find number of signs you gonna divide total distance by distance of a small sign
3/4 ÷ 1/12
= 3/4 × 12/1 = 3 × 3
therefore, the answer is 9 sign
Studies have shown that a high percentage of analytical models actually used in the business world are simply wrong.
What's a good strategy - which I've repeatedly emphasized in this class - to avoid depending on wrong answers?
(Limit your answer to 10 words of less.)
A good strategy to avoid depending on wrong answers is to conduct rigorous testing and validation.
In the business world, many analytical models are found to be incorrect, as studies have shown. To avoid relying on flawed answers, it is crucial to implement a strategy that emphasizes rigorous testing and validation. This involves thoroughly evaluating the model's performance by comparing its outputs with known or expected outcomes. By subjecting the model to various scenarios and testing its predictions against real-world data, discrepancies can be identified and corrected.
Regularly testing and validating analytical models helps to uncover potential flaws and inaccuracies. This iterative process allows for adjustments and improvements to be made, ensuring that the model provides reliable and accurate results. By implementing a robust testing and validation strategy, businesses can minimize the risks associated with using incorrect analytical models and make informed decisions based on reliable insights.
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A cylinder has a base diameter of 20 inches and a height of 11 inches. What is its
volume in cubic inches, to the nearest tenths place?
Step-by-step explanation:
Volume=base area * height
=πr^2h
22/7 * 10^2 *11
=3457.1cm3
Answer:
The volume of a cylinder with a diameter of 10 inches and height of 20 inches is 1,570.8 cubic inches.
What is the equation in standard form of
the line that passes through the points
(3, 5) and (-7, 2)?
Answer:
3x-10y=-41
Step-by-step explanation:
"standard form of the line" is ax+by=c, where a, b, and c are free coefficients
first, we need to find the slope (m) of the line
that is calculated with the formula (y2-y1)/(x2-x1)
we have the points (3,5) and (-7,2)
label the points:
x1=3
y1=5
x2=-7
y2=2
substitute into the equation
m=(2-5)/(-7-3)
m=-3/-10
m=3/10
the slope is 3/10
before we put a line into standard form, we need to put it into another form first-- like slope-intercept form (y=mx+b, where m is the slope and b is the y intercept)
we already know the slope
here's our line so far:
y=3/10x+b
we need to find b; since the line will pass through the points (3,5) and (-7,2) we can use either one of them to find b
let's use (3,5) as an example. Substitute into the equation
5=3/10(3)+b
5=9/10+b
41/10=b
b is 41/10
this is the equation:
y=3/10x+41/10
now we can find the equation in standard form. Subtract 3/10x from both sides
-3/10x+y=41/10
a (the number in front of x cannot be negative OR less than one. First, let's multiply both sides by -1)
3/10x-y=-41/10
multiply both sides by 10 to clear the fraction
3x-10y=-41
^^ is the equation
hope this helps!
PUT THEM IN ORDER PLEASE
Answer:
3,2,4, then 1
The 50th percentile of the numbers: 13. 10, 12, 10, 11 is
A. 125. B. 11 C. 10 D. 11.5
Answer:
B. 11
Step-by-step explanation:
The 50th percentile represents the halfway point of a data set and therefore, it is simply another name for the median.
We can use the following steps to find the median:
Step 1: Arrange the numbers in ascending numerical order:
10, 10, 11, 12, 13.
Step 2: Find the middle of the numbers:
Since there are 5 numbers, the median will have two numbers to the left and right of it. 11 satisfies this requirement so it is the median and thus the 50th percentile of the numbers.
please help me ..........
Answer:
It’s either A OR B
Step-by-step explanation:
PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!!PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!!
Answer:
hi
Step-by-step explanation:
hope it helps
have a nice day
Answer:
3.14, 5.8, 0.3, negative 2
Step-by-step explanation:
3.14 is found bn 2 and 3 but very close to 3 u can just take 3.1 and for 5.8 it's bn 5 and 6 very close to 6 but not six , and we'll negative 2 is right on negative 2
A function is defined by f(x) = x²+2, ≥0. A region R is enclosed by y = f(x), the y-axis line y = 4.
Find the exact volume generated when the region R is rotated through 27 radians about the y-axis.
Given that a function is defined by `f(x) = x² + 2`, and the region R is enclosed by `y = f(x)`, the `y-axis` line `y = 4`. We need to find the exact volume generated when the region R is rotated through `27 radians` about the `y-axis`.
Explanation: The formula for finding the volume generated by rotating the region R about the `y-axis` is given by: `V = ∫ [from a to b] 2πxf(x) dx`. Here, the value of `a` is `0` because it's given that `f(x) = x² + 2`, and `f(x)` is greater than or equal to `0`. Also, the line `y = 4` intersects `f(x)` at `x = 2`. So, the value of `b` is `2`.
Therefore, the volume generated is given by: V = ∫ [from 0 to 2] 2πx (x² + 2) dx`=`2π ∫ [from 0 to 2] (x³ + 2x) dx`=`2π [(x⁴/4) + x²] {from 0 to 2}`=`2π [(2⁴/4) + 2²] - 0`=`2π [4 + 4]`=`16π` cubic units.
So, the exact volume generated when the region R is rotated through `27 radians` about the `y-axis` is `16π` cubic units.
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Can I get help with number 16
Answer:
b
Step-by-step explanation:
Order the fractions from least to greatest.
1
-1.25, 0.125,
1
4
Answer:
-1.25, -1/4, -1/8, 0.125
Step-by-step explanation:
Answer:-1.25, -1/4, -1/8, 0.125
Step-by-step explanation:
What is the solution to this system of equations?
X+ 2y = 4
2x-2y = 5
0 (3.-52
0 (3.3
O no solution
infinitely many solutions
Answer:
3, 1/2
Step-by-step explanation:
x + 2y = 4
2x - 2y = 5
_______________ +
2x + x + 2y + (-2y) = 4 + 5
3x + 0 = 9
3x = 9
x = 9/3
x = 3
if you want to find the value of y, you just have to choose one of the equation. I will choose x + 2y = 4, even if you choose 2x - 2y = 5 the result remains same
x + 2y = 4
3 + 2y = 4
2y = 4 - 3
y = 1/2
x, y = 3, 1/2
#CMIIWi'm sorry, i'm not good at english ^^