Question

Issac tosses a quarter off of a bridge, creating the shape of a parabola. The parabola can be represented by the equation h=-16t^2-4t+20

c. How high is the coin after .25 seconds?

d. After how many seconds does it land on the ground?

Answer 1

Explanation:

a) the equation representing the parabola is expressed as

h = -16t² - 4t + 20

c) to determine the height after 25 seconds, we would substitute 25 for t into the given equation. It becomes

h = -16(25)² - 4(25) + 20

h = - 10000 - 100 + 20

h = - 10080

d) when the coin lands on the ground, the height would be 0. Therefore,

-16t² - 4t + 20 = 0

Dividing both sides of the equation by 4, it becomes

- 4t² - t + 5 = 0

- 4t² - 5t + 4t + 5 = 0

- t(4t + 5) + 1(4t + 5) = 0

- t + 1 = 0 or 4t + 5 = 0

t = 1 or t = - 5/4

Since t cannot be negative, then t = 1 second