document.write( "Question 692538: \"+g%28x%29=%28x%2B5%29%5E2+\", find all values of x for which g(x)=15 \n" ); document.write( "
Algebra.Com's Answer #427046 by mouk(232)\"\" \"About 
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\"+g%28x%29+=+15+\"
\n" ); document.write( "\"+%28x%2B5%29%5E2+=+15+\"
\n" ); document.write( "\"+%28x%2B5%29%28x%2B5%29+=+15+\"
\n" ); document.write( "\"+%28x%29%28x%29+%2B+5x+%2B+5x+%2B+%285%29%285%29+=+15+\"
\n" ); document.write( "\"+x%5E2+%2B+10x+%2B+25+=+15+\"
\n" ); document.write( "\"+x%5E2+%2B+10x+%2B+10+=+0+\"\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B10x%2B10+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%2810%29%5E2-4%2A1%2A10=60\".
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\n" ); document.write( " Discriminant d=60 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-10%2B-sqrt%28+60+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%2810%29%2Bsqrt%28+60+%29%29%2F2%5C1+=+-1.12701665379258\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2810%29-sqrt%28+60+%29%29%2F2%5C1+=+-8.87298334620742\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B10x%2B10\" can be factored:
\n" ); document.write( " \"1x%5E2%2B10x%2B10+=+1%28x--1.12701665379258%29%2A%28x--8.87298334620742%29\"
\n" ); document.write( " Again, the answer is: -1.12701665379258, -8.87298334620742.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B10%2Ax%2B10+%29\"
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