document.write( "Question 364090: the curve of a parabola passes through points (0,-4), (2,8) and (-2,0).Given that the axis of the parabola is parallel to y-axis.find the general equation of the parabola?.
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Algebra.Com's Answer #259688 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "*Note: stand form for the equation of a parabola:
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document.write( "y = ax^2 + bx + c  
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document.write( "Pt(0,4)tells us c = -4
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document.write( "y = ax^2 + bx - 4  
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document.write( "(2,8) and -2,0)
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document.write( "8 = 4a + 2b - 4 
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document.write( "0 = 4a - 2b - 4 
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document.write( "8 = 8a - 8
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document.write( "16 = 8a
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document.write( "a = 2
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document.write( "b = 2   (8 = 8 + 2b - 4 )
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document.write( "Y= 2x^2 + 2x - 4\r
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