What are the intercepts for y = 6x + 8?

1 Answer
Oct 7, 2015

We find this out by setting either x or y to zero and solving the equation

Explanation:

The x-intercept is the point on a line where it crosses the x (horizontal) axis. That is, y = 0 at that point

graph{y=6x+8 [-15.48, 6.72, -0.9, 10.2]}

So, if we set y = 0, the equation becomes

0 = 6x + 8

Solving for x by subtracting 8 from both sides of the equation:

-8 = 6x

and divide both sides by 6

- 8/6 = x

x = -1.333... -> this is the x-intercept

We can do the same thing for the y- intercept, which is the point where the line crosses the y (vertical axis), and x = 0

y = 6(0) + 8

y = 0 + 8

y = 8 ->. this is the y-intercept.

We can also take a shortcut... the equation of a line is:

y = m(x) + b

Where m is the slope of the line, and b is the y-intercept. So, in:

y = 6x + 8

The y-intercept is 8. Note that this only works when you have the equation in the form y = m(x) + b

Check the graph. Do these answers look about right? Does the line cross the x-axis at about -1.33? Does it cross the y-axis at around 8?