To solve systems of two equations with two variables (in this case, "x" and "y"), you choose one equation and attempt to solve for one of the variables.
For example, I will try solving for x using the first equation.
5x - 2y = 5
5x = 5 + 2y [move 2y to other side]
x = (5 + 2y) / 5 [divide both sides by 5]
x = 1 + (.4)y [simplified form]
Now, I plug this value into the x of the second equation to solve for y.
2x + 3y = 21
2 * (1 + (.4y)) + 3y = 21 [plug in x]
2 + (.8)y + 3y = 21 [distribute 2 to the x value we plugged in]
2 + 3.8y = 21 [add the y terms together]
3.8y = 19 [subtract 2]
y = 5 [divide by 5]
Now that we know the value of y, plug it into either of the original equations to find x. I'll plug it into the first one.
5x - 2y = 5
5x - 2(5) = 5 [plug in y]
5x - 10 = 5 [2 * 5]
5x = 15 [add 10]
x = 3 [divide by 5]
The final answer is x = 3, y = 5.
Answer:
A number
Step-by-step explanation:
it cant be nothing
Answer:
D. Circumference/Diameter = π
<em> hope this helps. good luck :)</em>
Answer:
That property would be associative
Step-by-.step explanation:
Because no matter how you change the parentheses in that problem, it would be the same.
Answer:
The test is left - tailed
We cannot reject the organization's claim ( its cheapest screens will truly last less than 2.8 years)
Step-by-step explanation:
Sample size, n = 61
Sample mean,
Standard deviation,
Significance level, α=0.02
Null hypothesis,
Alternative hypothesis,
It is clearly seen from the alternative hypothesis, that it is a left tailed test. It is not tailed towards the two directions.
Calculate the test statistic:
Calculate the P-value:
P(Z < -3.35) = 0.0002
Since (p-value = 0.0002) < (α=0.02), the null hypothesis is rejected.
It can therefore be concluded that the mean of the cheapest screen is less than 2.8 years. i.e. the cheapest screen will last less than 2.8 years