## Intermediate Algebra (6th Edition)

$f(x)=2x+16$
Using $y-y_1=\dfrac{y_1-y_2}{x_1-x_2}(x-x_1)$ or the Two-Point Form of linear equations, then the equation of the line passing through $(-9,-2) \text{ and } (-3,10) ,$ is \begin{array}{l}\require{cancel} y-(-2)=\dfrac{-2-10}{-9-(-3)}(x-(-9)) \\\\ y+2=\dfrac{-2-10}{-9+3}(x+9) \\\\ y+2=\dfrac{-12}{-6}(x+9) \\\\ y+2=2(x+9) \\\\ y+2=2x+18 \\\\ y=2x+18-2 \\\\ y=2x+16 .\end{array} In function notation, this is equivalent to $f(x)=2x+16 .$