Since the equation has the x-intercept -3 and the y-intercept -5, this means the equation goes through the points (-3,0) and (0,-5)
First lets find the slope through the points (
So the equation of the line which goes through the points (,) and (,) is:
The equation is now in
Notice if we graph the equation and plot the points (,) and (,), we get this: (note: if you need help with graphing, check out this solver)
When the equation is written in the slope-intercept form (y=mx+b) we can find the y-intercept by looking at the equation. The value of b is the y-intercept. This is because the y-intercept is when the x value equals 0. When x = 0, mx = 0, so when x = 0, y = b.
To find the x-intercept we set y = 0 and solve the equation for x. This is because when y=0 the line crosses the x-axis.
When an equation is not in y = mx + b form, we can solve for the intercepts by plugging in 0 as needed and solving for the remaining variable.
Video Source (08:37 mins) | Transcript
To find y-intercept: set x = 0 and solve for y. The point will be (0, y).
To find x-intercept: set y = 0 and solve for x. The point will be (x, 0).
Additional Resources
- Find the y-intercept of the line:
\({\text{y}}=-3{\text{x}}-9\) - Find the x-intercept of the line:
\({\text{y}}=-4{\text{x}}+12\) - Find the y-intercept of the line:
y − 9 = 3x - Find the x-intercept of the line:
y + 12 = 2x - Find the y-intercept of the line:
\({\text{x}}+6{\text{y}}=-24\) - Find the x-intercept of the line:
\(5{\text{x}}+4{\text{y}}=-20\)