Chapter 11 - Rational Expressions and Functions - 11-3 Dividing Polynomials - Practice and Problem-Solving Exercises - Page 683: 58

The answer is $10r^5+2r^4+5r^2$.

$(90r^6+28r^5+45r^3+2r^4+5r^2) \div (9r+1)$ $10r^5+2r^+5r^2$ _________________________ $9r+1) 90r^6+28r^5+45r^3+2r^4+5r^2$ $-90r^6-10r^5$ _________________________ $18r^5+2r^4 +45r^3$ $-18r^5-2r^4$ _________________________ $45r^3+5r^2$ $-45r^3-5r^2$ _________________________ $0$ The answer is $10r^5+2r^4+5r^2$.