Question

(4,a) and (2,5) are two points from a direct variation. what is a? use the step by step process you just learned to solve this problem. set up the correct type of variation equation. y= kx k/x x+k x-k​

Answer 1

Answer:

a = 10

Step-by-step explanation:

Since the quantities vary directly then the equation relating them is

y = kx ← k is the constant of variation

To find k use the point (2, 5 ) with x = 2 and y = 5

k = $\frac{y}{x}$ = $\frac{5}{2}$ = 2.5

y = 2.5x ← equation of variation

Using the point (4, a) with x = 4, then

y = a = 2.5 × 4 = 10

Answer 2

Answer:

Step-by-step explanation:

The variables are y and x

y ∞ x

y = kx

Where k is the constant of proportionality

Considering the first point

(4,a)

y = a and x = 4

a = 4k .......(1)

and (2,5)

y = 5 and x = 2

5 = 2k ..........(2)

k = 5/2

And a = 4k

a = 4(5/2)

a = 2×5

a = 10

The equation is

y = 5x/2