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

Question

Mathematics

Ingrid Gibson

1 November, 23:28

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

+4

Answers (1)

Know the Answer?

Soren Huerta · Answer 1

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!