The y-intercept is the point where the graph crosses the y-axis. It is found by setting x=0. For your equation, that makes the x-term vanish and only the constant remains. The ordered pair is ...
(x, y) = (0, -9)
So times $64.80 by 2.5. You minus 20 from that, so that the RacerZ is $142. You take that $142 and times that by 1.09. You get 154.78. Therefore;
Speedmonster- 64.80
RacerZ- 142
Swiftee-154.78
Hope this helps. :)
Maybe about 39% increase
try that, might be right.
The answer is y = -4
because the line is on the y-axis on -4. If it was x = -4 then the line would be vertical on -4 on the x-axis