Question

Jane and Jill want their mom to ride the rollercoaster with them, but she thinks it will be too fast. She asks the girls to find out how fast the rollercoaster will be travelling. They find out that the speed of the rollercoaster, in miles per hour, is modeled by the function g(x) = x4 - 4x2 + 7x - 8, where x is time measured in
seconds. How fast is the rollercoaster travelling at 2 seconds?
6 miles per hour
22 miles per hour
26 miles per hour
54 miles per hour

Answer 1

Answer:

Given that the function is a model of miles per hour with x being representative of time in seconds, you simply have to plug 2 into the equation for each x.

Therefore,

g(x) = x^4 - 4x^2 + 7x - 8

becomes

g(x) = 16 - 16 + 14 - 8 = 6 miles per hour.

So, 6 mph is your answer!!