Question

Simplify:

$36y^3(50y^2-98)÷26y^2(5y+7)$.

Answer 1

$36y^3(50y^2-98)÷26y^2(5y+7)$

$\Rightarrow \frac{36y^3(50y^2-98)}{26y^2(5y+7)}=\frac{18y^3(50y^2-98)}{13y^2(5y+7)}$

$=\frac{36y^{}(25y^2-49)}{13(5y+7)}=\frac{36y^{}\left[\right(5{y)}^2-{\left(7\right)}^2]}{13(5y+7)}$

$=\frac{36y^{}\left[(5y+7)(5y-7)\right]}{13(5y+7)}$ $[\because a^2-b^2=(a+b)(a-b)]$

$=\frac{36y^{}\left[(5y-7)\right]}{13}$