Question

Хелп sos капут . помогите

Answer 1

$\frac{b^2+2bc}{b+3}\cdot \frac{5b+15}{b^2-4ac}=\frac{b(b+2c)\cdot 5\cdot (b+3)}{(b+3)(b^2-4ac)}=\frac{5b(b+2c)}{b^2-4ac}$