So I need to determine what he did wrong is this problem and what the correct step would be?
WORTH 59 POINTS

The top line has 4x^-2, they needed to move the x^-2 to the denominator using the negative exponent rule, so in line 1 instead of 1/y^-2, it should be 1/x^-2
Then the answer would become 4y^3 / x^3