Let's simplify step-by-step.3x^2+5x−6−(−2x^2−6x+7)Distribute the Negative Sign:=3x^2+5x−6+−1(−2x^2−6x+7)=3x^2+5x+−6+−1(−2x^2)+−1(−6x)+(−1)(7)=3x^2+5x+−6+2x^2+6x+−7Combine Like Terms:=3x^2+5x+−6+2x^2+6x+−7=(3x^2+2x^2)+(5x+6x)+(−6+−7)=5x^2+11x+−13Answer:=5x^2+11x−13