Question 596198: A laboratory designed a radio telescope with a diameter of 280 feet and a maximum depth of 50 feet. the graph depicts a cross section of this telescope. find the equation of the parabola.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A laboratory designed a radio telescope with a diameter of 280 feet and a maximum depth of 50 feet. the graph depicts a cross section of this telescope. find the equation of the parabola.
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You could have a parabola passing through (-140,0),(0,280),(140,0)
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Form ax^2 + bx + c = y
Substitute each of the point values pairs to get 3 equations.
140^2a -140b + c = 0
0a + 0b + c = 280
140^2a + 140b + c = 0
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Solve the system to get:
a = -1/170
b = 0
c = 200
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y = (-1/170)x^2+280
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Cheers,
Stan H.
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