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21 votes
21 votes
A skateboarder leaves a 12-foot tall ramp with an initial vertical velocity of 8 feet per sen

function f(h) = -8t² +8t + 12 represents the height, h, in feet of the skateboarder after t seconds.
How many seconds was the skateboarder airbound

User MaxiReglisse
by
3.2k points

2 Answers

12 votes
12 votes

Answer:

Below in bold.

Explanation:

When he lands h = 0 so

-8t^2 + 8t + 12 = 0

Solving for t

t = [-8 +/- sqrt(8^2 - 3*-6*12)] / -16

t = 1.82 seconds.

User DeadlyJesus
by
2.8k points
10 votes
10 votes

To answer this, we substitute 12 ft to the f(h) in the given equation,
f(h) = -8t² + 8t + 12 = 12

Subtracting 12 from both sides of the equation will give us an answer of,

-8t² + 8t = 0

Then, we transpose 8 to the other side and divide the equation by -8 and t, we get an answer of t = 1 second.

User Nikhil Patil
by
2.7k points