y varies directly as w2. When y = 8, w = 2. Find y when w = 3
-
18
- 12
- 9
- 6
The correct answer is: A
Explanation
\(y \propto w^2\)y = kw2
8 = k(2)2
8 = k(4)
k = 8/4
k = 2
Thus y = 2w2
When w = 3, y = 2(3)2
y = 2 x 9 = 18
There is an explanation video available .