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

Jul 23, 2014

In an equation of the form $y = m x + b$, the y-intercept is "$b$"

The y-intercept is the $y$ value when $x$ is 0. It is the point on the y-axis where the line crosses it.

Let's see this through an example. Let's look at the equation:

$y = 4 x + 5$

Let's plug in 0 for x:

$y = 4 \cdot 0 + 5$
$y = 0 + 5$
$y = 5$

Which is the same as the value of "$b$" in the original equation.