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desperate! 15 its!

Tom throws a ball into the air. The ball travels on a parabolic path represented by the equation h = -8t 2 + 40t, where h represents the height of the ball above the ground and t represents the time in seconds.

How many seconds does it take the ball to reach its highest point?

What ordered pair represents the highest point that the ball reaches as it travels through the air?

Respuesta :

apologiabiology
highest poit is the vertex

to find vertex
convert to vertex form or something
or use hax way
in form
y=ax²+bx+c
the x value of the vertex is -b/2a
the y value is found by subsituting -b/2a for x

h=-8t²+40t+0
x value of vertex is  -40/(2*-8)=-40/-16=10/4=5/2

subsitute 5/2 for x
h=-8(5/2)²+40(5/2)
h=50

max height at 50 units
it take 5/2 or 2.5 seconds

ordered pair is (2.5,50) or (5/2,50)