In annual Student vs. Faculty Kickball game, Brian kicked a ball that was in the air for a total of 4.5 seconds before it landed on the ground. Assuming that the ball left from the ground (initial height=0) which of the following was the initial vertical velocity of the ball? HINT: Use the height equation for English units.

72.4004 ft/sec

Step-by-step explanation:

We know the parabola has width of 4.5 above the x-axis.

The parabola must face downward in order to represent a downward arc.

Therefore, the equation is:

-x^2+4.5x

The vertex is at (2.25, 5.063).

The max height was 5.063.

vy=v0y+ay⋅t

y=y0+v0y⋅t+12⋅ay⋅t2

explanation:

previous steps have made pa≅ pb ≅ st ≅ su. setting the compass width to ab allows you to make tu the same length. then δstu ≅ δpab by the sss congruence postulate, and ∠p ≅ ∠s by the reason cpctc.