What is 5 decreased by x

Olivia uses the work below to determine 55% of 720 which explains the error in olivia’s solution

Which ordered pair (c, d) is a solution to the given system of linear equations- c+2d=13 -9c-4d=-15

This is my question~~ ( r ^ 4 - 2r ^ 3 - 23 r ^ 2 - 4r - 32)÷(r+4) ~~ i must use long division to solve it : / i was wondering if anyone world like to solve it. and if so, share step-by-step explanations! you! ❤