SOLUTION: hello i\m chyrelle linn can you please help me with these question? during a televised football games, a parabolic microphone is used to capture sounds. The shield of the microp

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Question 1121083: hello i\m chyrelle linn can you please help me with these question?
during a televised football games, a parabolic microphone is used to capture sounds. The shield of the microphone is a paraboloid with a diameter of 18.75 inches and a depth of 3.66 inches. To pick up the sounds, a microphone is placed at the focus if the paraboloid. How far (to the nearest tenth of an inch) from the vertex of the paraboloid should the microphone be placed?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
y=ax%5E2
%281%2Fa%29y=x%5E2
Imagine the parabola cross section with vertex at (0,0) and concave up. A point is ( 9.375, 3.66 ).

4d=1%2Fa
and
%281%2Fa%29%2A3.66=9.375%5E2
1%2Fa=%289.375%5E2%29%2F3.66
1%2Fa=24.01383197=4d
d=6.0035
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Place the microphone at focus 6.0 inches above the vertex.