218k views
2 votes
PLEASE HELP! Drag each tile to the correct box.

The height of an object launched upward from ground level is given by the function s(t) = -4.9t2 + 78.4t, where s(t) is the height in meters and t is the time in seconds. Arrange the time intervals in ascending order of the object's magnitude of average velocity over the interval.

1 Answer

7 votes

Answer:

the distance of the object before it hits the ground after launch is t = 1.592 seconds

Explanation:

The height of an object launched upward from ground level is given by the function s(t) = -4.9t² +7.8t

when the object reach the ground then s(t) = 0

So; -4.9t² +7.8t = 0

-4.9t² +7.8t + 0 = 0

By using the quadratic equation


\mathbf{(-b \pm √(b^2-4ac) )/(2a)}

where; a = -4.9 ; b = 7.8 and c = 0


\mathbf{=(-(7.8) \pm √((7.8)^2-4(-4.9)(0)) )/(2(-4.9))}


\mathbf{=(-(7.8) \pm √((60.84) )/(-9.8)}


\mathbf{=(-(7.8) + √((60.84) )/(-9.8) \ \ \ \ OR \ \ \ \ \mathbf{(-(7.8) - √((60.84) )/(-9.8)}}


\mathbf{=0 \ \ \ OR \ \ \ 1.592 }}

Hence; the distance of the object before it hits the ground after launch is t = 1.592 seconds

User Alankar Srivastava
by
9.5k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.