document.write( "Question 131942: Solve
\n" ); document.write( "x^2+18x-4=0 \n" ); document.write( "

Algebra.Com's Answer #96318 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Complete the square. You do this by taking 1/2 of the coefficient of
\n" ); document.write( "the $\"x\"$ term, square it, then add that to both sides of the
\n" ); document.write( "equation. First, add $\"4\"$ to both sides
\n" ); document.write( " $\"x%5E2+%2B+18x+-+4+=+0\"$
\n" ); document.write( " $\"x%5E2+%2B+18x+%2B+%2818%2F2%29%5E2+=+4+%2B+%2818%2F2%29%5E2\"$
\n" ); document.write( " $\"x%5E2+%2B+18x+%2B+81+=+4+%2B+81\"$
\n" ); document.write( " $\"%28x+%2B+9%29%5E2+=+85\"$
\n" ); document.write( "Find square root of both sides
\n" ); document.write( " $\"x+%2B+9+=+sqrt%2885%29\"$
\n" ); document.write( "and
\n" ); document.write( " $\"x+%2B+9+=+-sqrt%2885%29\"$
\n" ); document.write( " $\"sqrt%2885%29+=+9.2195\"$
\n" ); document.write( " $\"x+%2B+9+=+9.2195\"$
\n" ); document.write( " $\"x+=+.2195\"$ answer
\n" ); document.write( "and
\n" ); document.write( " $\"x+%2B+9+=+-9.2195\"$
\n" ); document.write( " $\"x+=+-18.2195\"$ answer
\n" ); document.write( "check answers:
\n" ); document.write( " $\"x%5E2+%2B+18x+-+4+=+0\"$
\n" ); document.write( " $\"%28.2195%29%5E2+%2B+18%2A.2195+-+4+=+0\"$
\n" ); document.write( " $\".0482+%2B+3.951+-+4+=+0\"$
\n" ); document.write( " $\"3.9992+-4+=+0\"$
\n" ); document.write( "close enough
\n" ); document.write( " $\"%28-18.2195%29%5E2+-18%2A18.2195+-+4+=+0\"$
\n" ); document.write( " $\"331.95+-+327.951+-+4+=+0\"$
\n" ); document.write( " $\"3.999+-+4+=+0\"$
\n" ); document.write( "close enough \n" ); document.write( "

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