document.write( "Question 449383: Hey, Im in much need of help to figure out how to factor/solve qudaratic equations that are not in X^2+bx+c=0 form. for example,how do you factor 4x^2=4x+5? \n" ); document.write( "
Algebra.Com's Answer #309135 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
how do you factor 4x^2=4x+5?
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\n" ); document.write( "Rearrange:
\n" ); document.write( "4x^2 - 4x - 5 = 0
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\n" ); document.write( "Using the quadratic formula:
\n" ); document.write( "x = [4 +- sqrt(16-4*4*-5)]/(2*4)
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\n" ); document.write( "x = [4 +- sqrt(96)]/8
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\n" ); document.write( "x = [4 +- 4sqrt(6)]/8
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\n" ); document.write( "r1 = (1/2)+(1/2)sqrt(6) or r2 = (1/2)-(1/2)sqrt(6)
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\n" ); document.write( "Each of these is a root of the quadratic.
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\n" ); document.write( "The factored form would be (x-r1)(x-r2) = 0
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\n" ); document.write( "So the quadratic formula can ALWAYS be used to factor
\n" ); document.write( "a quadratic polynomial.
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\n" ); document.write( "If you are familiar with FOIL, Inverse FOIL can
\n" ); document.write( "be used to factor some quadratics.
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\n" ); document.write( "Example:
\n" ); document.write( " 2x^2+7x-15 = 0
\n" ); document.write( "ac = 2*-15 = -30
\n" ); document.write( "b = 7
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\n" ); document.write( "Think of 2 numbers whose product is ac and whose sum is b:
\n" ); document.write( "ac = 10*-3 = -30
\n" ); document.write( "b = 10+ -3 = 7
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\n" ); document.write( "Rewrite the quadratic replacing the \"b-term\":
\n" ); document.write( "2x^2 + 10x-3x -15 = 0
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\n" ); document.write( "Factor the 1st two and the last two terms separately:
\n" ); document.write( "2x(x+5)-3(x+5) = 0
\n" ); document.write( "Factor again:
\n" ); document.write( "(x+5)(2x-3) = 0
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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