document.write( "Question 101963: How do you solve this factor? \r
\n" ); document.write( "\n" ); document.write( "Factor: 5x^2 + 5x – 30 \n" ); document.write( "

Algebra.Com's Answer #74870 by Fombitz(32388) $\"\"$ $\"About$

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$\"5%2Ax%5E2%2B5x-30\"$ \r
\n" ); document.write( "\n" ); document.write( "First let's divide by 5 to see if it looks familiar.
\n" ); document.write( " $\"x%5E2+%2B+x+-+6=%28x%2Ba%29%28x%2Bb%29\"$
\n" ); document.write( "From the FOIL (First, Outer, Inner, Last) method, we know, \r
\n" ); document.write( "\n" ); document.write( " $\"%28x%2Ba%29%28x%2Bb%29=x%5E2+%2B+%28a%2Bb%29x+%2Ba%2Ab\"$
\n" ); document.write( "In our case,
\n" ); document.write( " $\"x%5E2+%2B+x+-+6=%28x%2Ba%29%28x%2Bb%29\"$
\n" ); document.write( "a + b =1
\n" ); document.write( "a*b=-6
\n" ); document.write( "The factors of 6 that are likely possible values are 2 and 3, let's get the signs right. Since a*b is negative, either a or b is negative. Since the sum is positive, the smaller one must be the negative one: a=3, b=-2.
\n" ); document.write( " $\"x%5E2+%2B+x+-+6=%28x%2Ba%29%28x%2Bb%29\"$
\n" ); document.write( " $\"x%5E2+%2B+x+-+6=%28x%2B3%29%28x-2%29\"$
\n" ); document.write( "To get back to your original equation we have to multiply by 5.
\n" ); document.write( " $\"5x%5E2+%2B+5x+-+30=5%28x%2B3%29%28x-2%29\"$ \n" ); document.write( "

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