document.write( "Question 299768: Factor completely. Show all work
\n" ); document.write( "7x2 + 11x – 30 \n" ); document.write( "

Algebra.Com's Answer #215293 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"7x%5E2+%2B+11x+-+30\"$
\n" ); document.write( "Use the quadratic formula
\n" ); document.write( " $\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"$
\n" ); document.write( " $\"a+=+7\"$
\n" ); document.write( " $\"b+=+11\"$
\n" ); document.write( " $\"c+=+-30\"$
\n" ); document.write( " $\"x+=+%28-11+%2B-+sqrt%28+11%5E2-4%2A7%2A%28-30%29+%29%29%2F%282%2A7%29+\"$
\n" ); document.write( " $\"x+=+%28-11+%2B-+sqrt%28+121+%2B+840+%29%29%2F14+\"$
\n" ); document.write( " $\"x+=+%28-11+%2B-+sqrt%28961%29%29%2F14+\"$
\n" ); document.write( " $\"x+=+%28-11+%2B+31%29%2F14\"$
\n" ); document.write( " $\"x+=+20%2F14\"$
\n" ); document.write( " $\"x+=+10%2F7\"$
\n" ); document.write( "and, also
\n" ); document.write( " $\"x+=+%28-11+-+31%29%2F14\"$
\n" ); document.write( " $\"x+=+-42%2F14\"$
\n" ); document.write( " $\"x+=+-3\"$
\n" ); document.write( "The factors are:
\n" ); document.write( " $\"%28x+-+10%2F7%29%2A%28x+-+%28-3%29%29+=+0\"$
\n" ); document.write( " $\"%28x+-+10%2F7%29%2A%28x+%2B+3%29+=+0\"$
\n" ); document.write( "check:
\n" ); document.write( "Multiplying these, I get
\n" ); document.write( " $\"x%5E2+-+%2810%2F7%29%2Ax+%2B+3x+-+30%2F7+=+0\"$
\n" ); document.write( "Multiply both sides by $\"7\"$
\n" ); document.write( " $\"7x%5E2+-+10x+%2B+21x+-+30+=+0\"$
\n" ); document.write( " $\"7x%5E2+%2B+11x+-+30+=+0\"$
\n" ); document.write( "OK \n" ); document.write( "

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