Question

The variables x and y vary directly. Write an equation that relates x and y. Then find what y equals when x = 12. ( x = 4, y = 8)

Answer 1

if x and y vary directly, then \[y = kx\] for some value of \(k\). Substitute your known values to determine \(k\), then put the value of \(k\) in \(y = kx\) to find the value of \(y\) when \(x = 12\)

Answer 2

Thank you. @whpalmer4

Answer 3

if they vary directly, they are proportional, so you can also find the value of y when x = 12 by multiplying the value of y when x = 4 by 12/4 to get the value of y when x = 12