Chapter 9 - Quadratic Functions and Equations - Cumulative Test Prep - Multiple Choice - Page 595: 11

A

$3n^2+10n+3$ is the area one side is $n+3$ $(n+3)(an+b)$ $an^2+bn+3an+3b$ $an^2+bn+3an+3b = 3n^2+10n+3$ $an^2=3n^2$ $an^2/n^2=3n^2/n^2$ $a=3$ $an^2+bn+3an+3b = 3n^2+10n+3$ $3n^2+bn+3*3n+3b = 3n^2+10n+3$ $3n^2+bn+9n+3b = 3n^2+10n+3$ $3n^2+bn+9n+3b = 3n^2+10n+3$ $bn+9n+3b = 10n+3$ $(b+9)n+3b=10n+3$ $b+9=10$ $b=1$ $an+b=3n+1$