Answer:
36
Step-by-step explanation:
For this case we have the following variables:
x: number of hours that it takes Mr. David to complete a job working alone.
y: number of hours it takes Mr. Ludwing to complete a job working alone.
k: number of hours it takes for both of them to do a job working together.
We now write the equation that models the problem.
To do this, we must add the work rate per hour of each and equal to the rate of work per hour of both.
![\frac{1}{x} +\frac{1}{y} =\frac{1}{k}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7Bx%7D%20%2B%5Cfrac%7B1%7D%7By%7D%20%3D%5Cfrac%7B1%7D%7Bk%7D%20%20)
We have then:
Answer:
The algebraic expression that models the problem is:
![\frac{1}{x} +\frac{1}{y} =\frac{1}{k}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7Bx%7D%20%2B%5Cfrac%7B1%7D%7By%7D%20%3D%5Cfrac%7B1%7D%7Bk%7D%20%20)
3x+3 = x-1
2x+3 = -1 (subtracted x from both sides)
2x = -4 (subtracted 3 from both sides)
x = -2 (divided 2 from both sides).
Answer:
2/5
Step-by-step explanation:
4÷2=2
10÷2=5
Answer:
The constant of variation is 2
Step-by-step explanation:
The equation of the direct variation is y = k x, where k is the constant of variation
<em>Let us solve the question</em>
∵ x and y are in the direct variation
→ Use the form of the equation above
∴ The equation of variation is y = k x
∵ x = 3
∵ y = 6
→ Substitute them in the equation above
∴ 6 = k (3)
∴ 6 = 3k
→ To find k divide both sides by 3
∵
= ![\frac{3k}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B3k%7D%7B3%7D)
∴ 2 = k
∵ k is the constant of variation
∴ The constant of variation is 2