The maximum speed reached is 89 km/h after 1.5 seconds.
<h3>Speed</h3>
Given the speed s
of the car in km/h, t seconds after the brakes were applied.
s(t) = -4t² + 12t + 80
a) The brakes were applied at t = 0, hence:
- s(0) = -4(0)² + 12(0) + 80 = 80 km/h
b) At s = 88:
88 = -4t² + 12t + 80
t = 2 seconds and t = 1 second
c) The maximum speed is at s'(t) = 0
s'(t) = -8 t + 12 = 0
8t = 12
t = 1.5 seconds
s(1.5) = -4(1.5)² + 12(1.5) + 80 = 89 km/h
The maximum speed reached is 89 km/h after 1.5 seconds.
Find out more on speed at: brainly.com/question/4931057