How do you evaluate a function f(x)=x+7 for a specific value, f(5)?

Nov 22, 2016

$f \left(5\right) = 12$

Explanation:

$\textcolor{b l u e}{x}$ is just a "place-holder" or "variable.

If $f \textcolor{b l u e}{x} = \textcolor{b l u e}{x} + 7$
then (using a different variable) $f \left(\textcolor{b l u e}{t}\right) = \textcolor{b l u e}{t} + 5$
or
using a constant $f \left(\textcolor{b l u e}{x}\right) = \textcolor{b l u e}{5} + 7$

Since $5 + 7 = 12$
for the given example $f \left(5\right) = 12$