Question 183·Easy·Advanced Math

Both coefficients are divisible by $5$, and both terms contain at least $y^2$, so the greatest common factor is $5y^2$. To find what belongs inside the parentheses, divide each term by it:

Divide the first term: its $y^4$ leaves $y^2$, not $y$:

Divide the second term to get $3$:

So:

For a Desmos check, type $x=5y^4-15y^2$ and $x=5y^2(y^2-3)$. Here $x$ shows each expression's output while $y$ stays the problem's variable. The curves overlap, matching the factorization. The equivalent expression is $5y^2(y^2-3)$. Choice A.