Question

If y varies directly as x and y=3 when x=2 find y when x=8​

Answer 1

12

Explanation:

x=2 was multiplied by 4 to get to x=8 so you multiply y=3 by 4 to make it y=12

Answer 2

y = 12 when x = 8

Explanation:

This is a case of direct variation, and the pertinent equation is y = kx.

Substituting 2 for x and 3 for y, we get: 3 = 2k. Then k = 3/2 is the constant of proportionality.

Then y = (3/2)x.

When x = 8, y = (3/2)(8) = 12