Jim decided to go for a drive in his car. He started out at 0 miles per hour (mph). He then

accelerated 20 mph down his street. Then, to get on the highway he accelerated another 35 miles

per hour. A car was going slow in front of him so he slowed down 11 mph. He then got off the

highway, so he slowed down another 7 mph. At what speed is he driving?

4 Miles per hour.

Step-by-step explanation:

Since he slowed down to 11 MPH at the slow car, We cab then use that as a baseline. They turned off the highway and slowed another 7 MPH, so we just subtract 7 from 11 to get 4 MPH.

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240