Question

Variables y and x have a proportional relationship, where y = 18 when x = 2.

Answer 1

Answer:

$\huge\boxed{\sf x = 4}$

Step-by-step explanation:

Given that:

$y \propto x$

Converting proportionality into equality

$y = kx$ ----------------(1)

y = 18 when x = 2

Put it in Eq. (1)

$\displaystyle 18 = k(2)\\\\Divide \ both \ sides \ by\ 2\\\\\frac{18}{2} = k\\\\9 = k\\\\ \boxed{k = 9}$

Now,

x = ? when y = 36

Put it in Eq. (1)

$36 = (9) x\\\\Divide \ both \ sides \ by \ 9\\\\36 / 9 = x\\\\4 =x \\\\\boxed{x = 4}\\\\\rule[225]{225}{2}$