suppose that y varies directly with x, and y =8 when x = 20

Question

find y when x = 7

write a direct variation equation that relates x and y

Answer 1

In a direct variation, the general formula is y=k*x, where k is a constant. They tell you that when x=20, then y=8, so you can use this information to solve for k. After you solve for k, then you would write the general formula again only you would substitute the number you found in for k, and that's it!