Question

How do you write a direct variation equation if y=36 when x=9, and how do you find x when y=52?

Answer 1

Write your equation as `y=kx` where `k` is the constant of proportionality that you have to find:
find `k` substituting `x=9` and `y=36` to get:
`36=9k` determine `k` by rearranging it and you'll have a complete equation `y=kx`;
Plug into your equation `y=52` to get:
`x=....`