Asubmarine was at a depth of 225 meters below sea level. it rose 80 meters, then it dove 35 meters. how far below sea level was the submarine after ascending and descending

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! ❤