Answer
$$\frac {15y^3}{x^{8}}$$
Work Step by Step
We first find the given formula, which is given by the area of the parallelogram.
$$ A = \frac{3x^{-1}}{y^{-3}} \times 5x^{-7} $$
We use the rules found in this chapter:
$$ a^b \times a ^c = a ^ {b+c}$$
$$ \frac {a^b}{a^c} = a ^ {b-c}$$
$$ a ^ {b^c} = a^{bc}$$
This gives:
$$ \frac {15y^3}{x^{7+1}}=\frac {15y^3}{x^{8}}$$
