Precalculus: Mathematics for Calculus, 7th Edition

$-x^3+2y+3y^2$
$Factor$ $out$ $the$ $common$ $factor:$ $-7x^4y^2+14xy^3+21xy^4$ All the terms have a common factor of $7xy^2$ $\frac{-7x^4y^2}{7xy^2} = -x^3$ $\frac{14xy^3}{7xy^2} = 2y$ $\frac{21xy^4}{7xy^2} = 3y^2$ $=-x^3+2y+3y^2$