# If a=12, b=9, and c=4, what is (b^2-2c^2)/(a+c-b)?

Mar 30, 2018

See a solution process below:

#### Explanation:

Substitute:

• $\textcolor{red}{12}$ for each occurrence of $\textcolor{red}{a}$
• $\textcolor{b l u e}{9}$ for each occurrence of $\textcolor{b l u e}{b}$
• $\textcolor{g r e e n}{4}$ for each occurrence of $\textcolor{g r e e n}{c}$

and then calculate the result:

$\frac{{\textcolor{b l u e}{b}}^{2} - 2 {\textcolor{g r e e n}{c}}^{2}}{\textcolor{red}{a} + \textcolor{g r e e n}{c} - \textcolor{b l u e}{b}}$ becomes:

$\frac{{\textcolor{b l u e}{9}}^{2} - \left(2 \cdot {\textcolor{g r e e n}{4}}^{2}\right)}{\textcolor{red}{12} + \textcolor{g r e e n}{4} - \textcolor{b l u e}{9}} \implies$

$\frac{81 - \left(2 \cdot 16\right)}{16 - \textcolor{b l u e}{9}} \implies$

$\frac{81 - 32}{7} \implies$

$\frac{49}{7} \implies$

$7$