Question

$\frac{b ^{2} -16 }{3b + 6} \div \frac{2b + 8}{5b + 10} =$
пожалуйста помогите пжпжпж​

Answer 1

$\displaystyle\bf\\\frac{b^{2}-16 }{3b+6}:\frac{2b+8}{5b+10} =\frac{b^{2} -16}{3b+6} \cdot\frac{5b+10}{2b+8} =\\\\\\=\frac{(b-4)(b+4)}{3\cdot(b+2)} \cdot\frac{5\cdot(b+2)}{2\cdot(b+4)}=\frac{5\cdot(b-4)}{6} =\frac{5b-20}{6}$