y varies directly with the square x If y32 when x4 find y

y varies directly with the square x . If y=32 when x=4 , find y when x=3 .

Solution

y varies directly with square of x.

Means we could write this statement in equation.

y = k x^2

where k is just a constant that makes the equation true.

Now as per given condition, If y=32 when x=4. Putting these value in previous equation.

32 = k . 4^2

32 = k * 16

k = 2

When x = 3,

y = k x^2

y = 2 * 3^2

y = 2 * 9

y = 18 Answer.