Chapter 5 - Exponents and Polynomials - 5.1 - Addition and Subtraction of Polynomials - Problem Set 5.1 - Page 195: 19

$2x^2-2x-23$

We write an expression to express this addition problem: $-2x^2+7x-9+(4x^2-9x-14)$ We use the commutative and associative properties of addition to group like terms: $(-2x^2+4x^2)+(7x-9x)+(-9-14)$ We combine the like terms: $2x^2+(-2x)+(-23)=2x^2-2x-23$