document.write( "Question 971171: Can you help me find the equation of parabola axis vertical
\n" ); document.write( "phases through (-1,0), (5,0), (1,8)? \n" ); document.write( "

Algebra.Com's Answer #593731 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "Can you help me find the equation of parabola axis vertical
\n" ); document.write( "phases through (-1,0), (5,0), (1,8)?
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General form of quadratic equation: \r
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document.write( " ------- Using (- 1, 0) in general quadratic equation
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document.write( " ------ eq (i)\r
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document.write( " ------- Using (5, 0) in general quadratic equation
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document.write( " ------ eq (ii)\r
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document.write( " ------- Using (1, 8) in general quadratic equation
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document.write( " ------ eq (iii)\r
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document.write( "- 2b = - 8 --------- Subtracting eq (iii) from eq (i)
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document.write( ", or b = 4 \r
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document.write( " ------- Substituting 4 for b in eq (i)
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document.write( "a = 4 - c ------- eq (iv)\r
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document.write( "25(4 - c) + 5(4) + c = 0 ------ Substituting 4 - c for a, and 4 for b in eq (ii)
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document.write( "100 - 25c + 20 + c = 0
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document.write( "- 25c + c + 120 = 0
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document.write( "- 24c = 0 - 120
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document.write( "- 24c = - 120
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document.write( ", or c = 5 \r
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document.write( "a = 4 - 5 ------- Substituting 5 for c in eq (iv)
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document.write( "a = - 1\r
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document.write( "Therefore,
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document.write( "a = - 1
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document.write( "b = 4
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document.write( "c = 5\r
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document.write( "General quadratic equation:  now becomes:
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