You can
put this solution on YOUR website!The y-intercept is the easy one, so let's start there. The point where a function intersects the y-axis ALWAYS has an x-coordinate of 0 (to plot the point, you haven't moved left or right at all, you've only moved up or down). Thus, to find the y-intercept, we can just plug in 0 for x.
So, the y-intercept is the point (0, 24)
To find the x-intercept, we do the opposite and plug 0 in for y:
. I hate having a negative in front of the
term, so let's divide everything by -1 (this will essentially change all the signs; 0 will still be 0 because 0 divided by -1 is still 0).
Now, we have
. This is factorable if we use -8 and 3 (
, the middle term, and
, the last term). So it can be re-written as
.
Recall that if two things multiply to 0, one of them must be 0 (for example, if
, then x=0). Thus, either
or
. If you solve each for x, you get x=8 or x=-3. Those are the two solutions when y=0, so those are the two x-intercepts: (8, 0) and (-3, 0).
