If f(x)=3x-4 and g(x)=x^2, how do you find the value of f(3)-g(2)?

1 Answer
Jan 5, 2017

See complete process below:

Explanation:

First, we can find the formula for the subtraction without substitution:

$f \left(\textcolor{red}{x}\right) - g \left(\textcolor{b l u e}{x}\right) = \left(3 \textcolor{red}{x} - 4\right) - {\textcolor{b l u e}{x}}^{2}$

We can now substitute the values for the functions:

$f \left(\textcolor{red}{3}\right) - g \left(\textcolor{b l u e}{2}\right) = \left(\left(3 \times \textcolor{red}{3}\right) - 4\right) - {\textcolor{b l u e}{2}}^{2}$

We can now solve the equation:

$f \left(\textcolor{red}{3}\right) - g \left(\textcolor{b l u e}{2}\right) = \left(9 - 4\right) - 4$

$f \left(\textcolor{red}{3}\right) - g \left(\textcolor{b l u e}{2}\right) = 5 - 4$

$f \left(\textcolor{red}{3}\right) - g \left(\textcolor{b l u e}{2}\right) = 1$