document.write( "Question 622083: What is the equation, in standard form, of a parabola that models the values in the table?\r
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Algebra.Com's Answer #391110 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( "x	f(x)
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document.write( "-2	-7
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document.write( "0	3
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document.write( "4	-73
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document.write( " f(x) = ax^2 + bx  + c
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document.write( " f(0) = ax^2 + bx  + c = 3, c = 3
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document.write( " f(-2) = 4a + -2b + 3 = -7
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document.write( " f(4)  =16a + 4b + 3 = -73
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document.write( " 4a  -2b = -10   ||multiplying by 2 and adding to the 2nd EQ to eliminate b
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document.write( "16a + 4b = -76 
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document.write( "      24a = -96
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document.write( "        a = -4   and b = -3   (-16 -2b = -10, -2b = 6, b = -3)
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document.write( "f(x) = -4x^2 - 3x + 3 \n" );
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