document.write( "Question 1186777: Let f(x)=x^2 +8x\r
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Algebra.Com's Answer #817731 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=x%5E2+%2B8x\"$ \r
\n" ); document.write( "\n" ); document.write( "Solve $\"f%28x%29=-16\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-16=x%5E2+%2B8x\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"0=x%5E2+%2B8x%2B16\"$ .........write as a square of the sum \r
\n" ); document.write( "\n" ); document.write( " $\"0=x%5E2+%2B8x%2B4%5E2\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"0=%28x%2B4%29%5E2\"$ \r
\n" ); document.write( "\n" ); document.write( "solution:\r
\n" ); document.write( "\n" ); document.write( " $\"0=%28x%2B4%29\"$ => $\"x=-4\"$ \r
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