document.write( "Question 178400This question is from textbook
\n" ); document.write( ": Use the quadratic formula to solve: -x^2+7x-10=0 \n" ); document.write( "

Algebra.Com's Answer #133350 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"-x%5E2+%2B+7x+-+10+=+0\"$
\n" ); document.write( "When the equation is in the form
\n" ); document.write( " $\"ax%5E2+%2B+bx+%2B+c+=+0\"$ , you can use the
\n" ); document.write( "quadratic formula which is:
\n" ); document.write( " $\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"$
\n" ); document.write( " $\"a+=+-1\"$
\n" ); document.write( " $\"b+=+7\"$
\n" ); document.write( " $\"c+=+-10\"$
\n" ); document.write( " $\"x+=+%28-7+%2B-+sqrt%28+7%5E2-4%2A%28-1%29%2A%28-10%29+%29%29%2F%282%2A%28-1%29%29+\"$
\n" ); document.write( " $\"x+=+%28-7+%2B-+sqrt%28+49+-+40+%29%29%2F%28-2%29+\"$
\n" ); document.write( " $\"x+=+%28-7+%2B-+sqrt%28+9+%29%29%2F%28-2%29+\"$
\n" ); document.write( "The 2 answers are:
\n" ); document.write( " $\"x+=+%287+-+3%29+%2F+2\"$
\n" ); document.write( " $\"x+=+2\"$
\n" ); document.write( "and
\n" ); document.write( " $\"x+=+%287+%2B+3%29+%2F+2\"$
\n" ); document.write( " $\"x+=+5\"$
\n" ); document.write( "I can see directly that this is true, since
\n" ); document.write( " $\"-x%5E2+%2B+7x+-+10+=+%28-x+%2B+5%29%28x+-+2%29\"$
\n" ); document.write( "and
\n" ); document.write( " $\"%28-x+%2B+5%29%28x+-+2%29+=+0\"$
\n" ); document.write( " $\"%28-5+%2B+5%29%285+-+2%29+=+0\"$
\n" ); document.write( " $\"0%2A3+=+0\"$
\n" ); document.write( " $\"0+=+0\"$
\n" ); document.write( " $\"%28-2+%2B+5%29%282+-+2%29+=+0\"$
\n" ); document.write( " $\"3%2A0+=+0\"$
\n" ); document.write( " $\"0+=+0\"$ \n" ); document.write( "

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