Question 1039289: Please help me solve this question!A giant parabolic dish has a diameter of 400 meters and a depth of 80 meters. Find an equation in the form that describes a cross-section of this dish
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Please help me solve this question!A giant parabolic dish has a diameter of 400 meters and a depth of 80 meters. Find an equation in the form that describes a cross-section of this dish
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A cross-section is a parabola.
Sketch the parabola on an x/y coordinate plane::
x-intercepts:: -200,0 and +200,0
y-intercept:: 0,80
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Form:: y = a(x-h)^2+k
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Since the vertex is (0,80), h = 0, k = 80
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Using (200,0), solve for "a"::
0 = a(200-0)^2 + 80
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0 = 40000a + 80
a = -0.002
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Equation::
y = (-0.002)x^2 + 80
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Cheers,
Stan H.
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