# Line equation

1. Dec 6, 2014

### Rectifier

The problem

Find k and m.

$f(x) = kx+m$

$f(3x-2)=6x-5$

The attempt

$t = 3x - 2$

$f(t) = kt + m \\ f(3x -2) = 2(3x-2) - 1 \\ f(t) = 2t - 1 \\ f(t) = kt + m \\ k=2 \\ m=-1$

I am not sure if I am doing this right...

2. Dec 6, 2014

### mafagafo

You can numerically test your work. Do it.

Checking your work numerically (when possible) is a good way to check your calculations even if you think you are doing it right.