Question

Answer, please. I need help.

Answer 1

1/ b^4

Explanation:

because -7 +3 = -4 but it can only be positive. So you but the -4 to the bottom to become b^4

Answer 2

Explanation:

`\text{rule }(x^a)(x^b)=x^((a+b))\\ \\ (b^(-7))(b^3)=b^((-7+3))\\ \\ b^(-4)=(1)/(b^4)`