Question

Find the factors.

(13) 3x² + 3xy − 1260y²

Answer 1

The factors of 3x² + 3xy − 1260y² are:

$$\begin{gathered} 3x^2+3xy-1260y^2 \\ =3\left[x^2+xy-420y^2\right] \\ =3\left[x^2+21xy-20xy-420y^2\right] \\ =3\left[x\left(x+21y\right)-20y\left(x+21y\right)\right] \\ =3\left(x+21y\right)\left(x-20y\right) \end{gathered}$$