document.write( "Question 83827: Solve by using the quadratic formula.
\n" ); document.write( " x^2 = –7x + 12 \n" ); document.write( "

Algebra.Com's Answer #60295 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"x%5E2+=+-7x+%2B+12+\"$
\n" ); document.write( " $\"x%5E2+%2B+7x+-+12+=+0\"$
\n" ); document.write( "This is now in the form
\n" ); document.write( " $\"ax%5E2+%2B+bx+%2B+c+=+0\"$
\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 = -12
\n" ); document.write( " $\"x+=+%28-7+%2B-+sqrt%28+7%5E2-4%2A1%2A%28-12%29+%29%29%2F%282%2A1%29+\"$
\n" ); document.write( " $\"x+=+%28-7+%2B-+sqrt%2897%29%29%2F2+\"$
\n" ); document.write( "The answers are:
\n" ); document.write( " $\"x+=+%28-7+%2B+sqrt%2897%29%29+%2F+2\"$
\n" ); document.write( "and
\n" ); document.write( " $\"x+=+%28-7+-+sqrt%2897%29%29+%2F+2\"$
\n" ); document.write( "You can check these answers by substituting for x in the
\n" ); document.write( "equation, but it's tough algebra. Instead, you can
\n" ); document.write( "evaluate $\"sqrt%2897%29+=+9.849\"$ and find the roots
\n" ); document.write( " $\"x=+1.424\"$ and $\"x+=+-8.425\"$
\n" ); document.write( " $\"x%5E2+=+-7x+%2B+12+\"$
\n" ); document.write( " $\"%281.424%29%5E2+=+-7%2A%281.424%29+%2B+12\"$
\n" ); document.write( " $\"2.028+=+-+9.968+%2B+12\"$
\n" ); document.write( " $\"2.028+=+2.032\"$ Not exact due to rounding-off errors,
\n" ); document.write( "but you get the idea \n" ); document.write( "

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