You would multiply the sales regular price by the percent and then subtract your answer from the regular sale price. For example, if something cost $499 and the sales price was 15% off, you would multiply 499 by 0.15 and then you would get 74.85.
We first find the lines of the motion of each truck, then calculate its intercept.
Garbage truck:
m = (12 - 4) / (5 - 3)
m = 4
4 - y = 4(3 - x)
4x - y = 8
Dump truck:
m = (33 + 3) / (-4 - 5)
m = -4
33 - y = -4(-4 - x)
4x + y = 17
Adding the two equations to solve them, we get:
8x = 25
x = 25 / 8
y = 17 - 4(25/8)
y = 17 - 25/2
y = 9/2
The trucks' point of intersection is (25/8,9/2)
Answer:
90 km an hour.
Step-by-step explanation:
