Question 956636: The dimensions of the facade of the house, should be 7m wide and 4 ms high, it should be a parabola, use the origin of the parabola as one corner. Find the quadratic equation to that.
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3 points are (0,0), (3.5,4) and (7,0)
y = ax^2 + bx + c
At x = 0, y = 0 --> c = 0
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At x = 7, y = 0
49a + 7b = 0
7a + b = 0
b = -7a
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At x = 3.5, y = 4
12.25a + 3.5b = 4
Sub for b
12.25a - 24.5a = 4
-12.25a = 4
a = -16/49
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b = 16/7
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And then they got
y=16x^2/49+16x/7
I do not understand the process here, I am practicing for my exam and this on the practice exam, could someone please explain the process clearly to me? That would be greatly appreciated
Answer by Fombitz(32388)   (Show Source):
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