y=x4-x2

Rewrite 4 as 22.

y=x22-x2

Since both terms are perfect squares, factor using the difference of squares formula, a2-b2=(a+b)(a-b) where a=2 and b=x.

y=x(2+x)(2-x)

y=x(2+x)(2-x)

The given equation y=x(2+x)(2-x) can not be written as y=kx2, so y doesn’t vary directly with x2.

y doesn’t vary directly with x

Find the Quadratic Constant of Variation y=x square root of 4-x^2