# How do I find the x-intercept of an equation in the form y = mx + b?

Oct 7, 2014

The coordinates of a line or point on the x-axis will always have a $y$ coordinate of $0$.

The following are examples of coordinates that lie on the $x$-axis.

$\left(- \frac{3 \pi}{2} , 0\right)$
$\left(0 , 0\right)$ the origin
$\left(- 2 , 0\right)$
$\left(3 , 0\right)$
$\left(\frac{\pi}{2} , 0\right)$

To find the $x$-intercept you would substitute in the value of $0$ for $y$ variable and then solve for the $x$ variable.

Example:

$y = 2 x + 6$

$0 = 2 x + 6$

$- 6 = 2 x$

$- \frac{6}{2} = \frac{2 x}{2}$

$- 3 = x$

$\left(- 3 , 0\right) \to$ The y-intercept