SOLUTION: A tennis ball is served from a height of 7 feet to just clear a net 3 feet high. If it served from a line 39 feet behind the net and travels in a straight path, how far from the ne

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Question 109611: A tennis ball is served from a height of 7 feet to just clear a net 3 feet high. If it served from a line 39 feet behind the net and travels in a straight path, how far from the net does the ball first hil the ground?
The answer is 29.25 in the answer key, I just need to know how to do it!
PLEASE HELP- NEED SOON!
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A tennis ball is served from a height of 7 feet to just clear a net 3 feet high. If it served from a line 39 feet behind the net and travels in a straight path, how far from the net does the ball first hil the ground?
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Draw the picture.
It is a right triangle with vertical side of 7 ft. and a parallel net that
is 3 ft hight.
The line segment from the net to the service line is 39 ft.
Let the distance from the net to where it hits the ground be "x" ft.
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You have two similar right triangles:
Set up the following proportion and solve for "x":
x/(x+39) = 3/7
7x = 3x+117
4x = 117
x = 117/4 ft
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In the smaller of the two rt. triangles
you have the base = (117/4) = 29.25 ft
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Cheers,
Stan H.