document.write( "Question 406079: Use the following quadratic equation to complete parts a and b below. You must show all work.\r
\n" ); document.write( "\n" ); document.write( "x2 + 4x - 21 = 0\r
\n" ); document.write( "\n" ); document.write( "a. Solve by factoring.
\n" ); document.write( "b. Solve using the quadratic formula.
\n" ); document.write( "

Algebra.Com's Answer #286656 by stanbon(75887)\"\" \"About 
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x^2 + 4x - 21 = 0
\n" ); document.write( "a. Solve by factoring.
\n" ); document.write( "x^2+7x-3x-21 = 0
\n" ); document.write( "x(x+7)-3(x+7) = 0
\n" ); document.write( "(x+7)(x-3) = 0
\n" ); document.write( "x = -7 or x = 3
\n" ); document.write( "=============================================
\n" ); document.write( "b. Solve using the quadratic formula.
\n" ); document.write( "x = [-4 +- sqrt(16 - 4*1*-21)]/2
\n" ); document.write( "---
\n" ); document.write( "x = [-4 +- sqrt(16+84)]/2
\n" ); document.write( "---
\n" ); document.write( "x = [-4 +- 10]/2
\n" ); document.write( "---
\n" ); document.write( "x = [-2+- 5]
\n" ); document.write( "---
\n" ); document.write( "x = -7 or x = 3\r
\n" ); document.write( "\n" ); document.write( "===================
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "===============
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