# Let F(x)=x^2-20 and G(x)=14-x, how do you find (F/G)(7)?

Apr 9, 2017

https://www.mathsisfun.com/sets/functions-operations.html

See the entire solution process below:

#### Explanation:

First,

$\left(\frac{F}{G}\right) \left(x\right) = \frac{{x}^{2} - 20}{14 - x}$

To find $\left(\frac{F}{G}\right) \left(7\right)$ we need to substitute $\textcolor{red}{7}$ for each occurrence of $\textcolor{red}{x}$ in $\left(\frac{F}{G}\right) \left(x\right)$:

$\left(\frac{F}{G}\right) \left(\textcolor{red}{x}\right) = \frac{{\textcolor{red}{x}}^{2} - 20}{14 - \textcolor{red}{x}}$ becomes:

$\left(\frac{F}{G}\right) \left(\textcolor{red}{7}\right) = \frac{{\textcolor{red}{7}}^{2} - 20}{14 - \textcolor{red}{7}}$

$\left(\frac{F}{G}\right) \left(\textcolor{red}{7}\right) = \frac{49 - 20}{7}$

$\left(\frac{F}{G}\right) \left(\textcolor{red}{7}\right) = \frac{29}{7}$