# Linear Function Formula

A linear function is a polynomial function whose graph gives a straight line. The linear function formula is of the form.

$\large y=f(x)=mx+c$

Here x is independent variable, Y is dependent variable, m is slope and c is intercept.

Suppose the equation of line passes through the points (x1,y1) and (x2,y2) in a graph then the linear function is given by

$\large y_{2}-y_{1}=m(x_{2}-x_{1})$

Then the slope m is given by

$\large m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

### Solved Examples

Question 1: Solve: 3x + 5 = 0

Solution:

Given function is 3x + 5 = 0
3x + 5 = 0
3x = -5
x = $\frac{-5}{3}$ = – 1.667