# How do you simplify -10/21(-36/15)?

$\frac{- 10 \times - 36}{21 \times 15} = \frac{360}{315} = \frac{45 \times 8}{45 \times 7} = \frac{\textcolor{red}{\cancel{\textcolor{b l a c k}{45}}} \times 8}{\textcolor{red}{\cancel{\textcolor{b l a c k}{45}}} \times 7} = \frac{8}{7}$