Answer
$3x^{2}+x+18$
Work Step by Step
We are given the expression $(5x^{2}+x+9)-(2x^{2}-9)$. We can subtract the second polynomial from the first polynomial by adding the opposite of the second polynomial to the first polynomial.
$(5x^{2}+x+9)+(-2x^{2}+9)$
We can combine like terms to simplify.
$(5x^{2}-2x^{2})+x+(9+9)=3x^{2}+x+18$
