Replace f(x) with y. Then swap x and y. Once the swap has been done, solve for y to get the inverse.
[tex]f(x) = -14x - 2 [/tex]
[tex]y = -14x - 2 [/tex]
[tex]x = -14y - 2 [/tex]
[tex]x+2 = -14y [/tex]
[tex]-14y = x+2 [/tex]
[tex]y = -\frac{x+2}{14} [/tex]
[tex]f^{-1}(x) = -\frac{x+2}{14} [/tex]
