# How do you reduce 7y + 2y^2 - 7 by 3 - 4y?

Jun 24, 2015

$11 y + 2 {y}^{2} - 10$ is $\left(3 - 4 y\right)$ less than $7 y + 2 {y}^{2} - 7$;
that is, if you reduce $7 y + 2 {y}^{2} - 7$ by $3 - 4 y$ you get $11 y + 2 {y}^{2} - 10$

#### Explanation:

The phrasing is a little unusual but "reducing" A by B means subtracting B from A.

$\left(\textcolor{red}{7 y + 2 {y}^{2} - 7}\right) - \left(\textcolor{b l u e}{3 - 4 y}\right)$

$= \textcolor{red}{7 y} \textcolor{b l u e}{+ 4 y} + 2 {y}^{2} \textcolor{red}{- 7} \textcolor{b l u e}{- 3}$

$= 11 y - 2 {y}^{2} - 10$