# How do you simplify ( 5x^2 Z) (-2xz^3)?

Here you can use the fact that ${x}^{m} \cdot {x}^{n} = {x}^{m + n}$ so you get:
$\left(5 \cdot - 2\right) \left({x}^{2} \cdot x\right) \left(z \cdot {z}^{3}\right) = - 10 {x}^{2 + 1} {z}^{1 + 3} = - 10 {x}^{3} {z}^{4}$