document.write( "Question 309113: how would you solve for 7d squared +50d +7 \n" ); document.write( "
Algebra.Com's Answer #221007 by Stitch(470)\"\" \"About 
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Given: \"7D%5E2+%2B+50D+%2B+7\"
\n" ); document.write( "Set the equation equal to 0.
\n" ); document.write( "Then use the quadratic equation
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"aD%5E2%2BbD%2Bc=0\" (in our case \"7D%5E2%2B50D%2B7+=+0\") has the following solutons:
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\n" ); document.write( " \"D%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=%2850%29%5E2-4%2A7%2A7=2304\".
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\n" ); document.write( " Discriminant d=2304 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-50%2B-sqrt%28+2304+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"D%5B1%5D+=+%28-%2850%29%2Bsqrt%28+2304+%29%29%2F2%5C7+=+-0.142857142857143\"
\n" ); document.write( " \"D%5B2%5D+=+%28-%2850%29-sqrt%28+2304+%29%29%2F2%5C7+=+-7\"
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\n" ); document.write( " Quadratic expression \"7D%5E2%2B50D%2B7\" can be factored:
\n" ); document.write( " \"7D%5E2%2B50D%2B7+=+7%28D--0.142857142857143%29%2A%28D--7%29\"
\n" ); document.write( " Again, the answer is: -0.142857142857143, -7.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+7%2Ax%5E2%2B50%2Ax%2B7+%29\"

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\n" ); document.write( "The other way is to unfoil the equation
\n" ); document.write( "\"7D%5E2+%2B+50D+%2B+7+=+0\"
\n" ); document.write( "Find the factors of 7: 1,7
\n" ); document.write( "Use the factors of 7 & 1 with the coefficient of the D^2 to get 50
\n" ); document.write( "7*7 + 1 = 50
\n" ); document.write( "Rewrite the equation
\n" ); document.write( "\"%287D+%2B+1%29%2A%28D+%2B+7%29\"
\n" ); document.write( "Set each factor to 0 and solve for D
\n" ); document.write( "\"7D+%2B+1+=+0\"
\n" ); document.write( "\"7D+=+-1\"
\n" ); document.write( "\"highlight%28D+=+-1%2F7%29\"
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\n" ); document.write( "\"D+%2B+7+=+0\"
\n" ); document.write( "\"highlight_green%28D+=+-7%29\"
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