Question

Abraham throws a ball from a point 40 m above the ground.The height of the ball from the ground level after t seconds is defined by the function h(t)=40t-5t. how long will the ball take to hit the ground

Answer 1

T = 4-2 √2

Explanation:

The given function is:

h(t)=40t-5t²

Let h(t)=40

We get,

40t-5t²=40

5t²-40t+40=0

t²-8t+8=0

(t-4)²=8

t-4=±√8

t=±√8+4

t=√8+4; t=4-√8

By considering the reality we know t>0t:

4-2√2

Thus the answer to your problem is, 4-2 √2