document.write( "Question 307133: use any method to solve the equation 7x^2-16x-28=0 \n" ); document.write( "
Algebra.Com's Answer #219704 by Stitch(470)\"\" \"About 
You can put this solution on YOUR website!
You can use the quadratic equatiion:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"7x%5E2%2B-16x%2B-28+=+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=%28-16%29%5E2-4%2A7%2A-28=1040\".
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\n" ); document.write( " Discriminant d=1040 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--16%2B-sqrt%28+1040+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-16%29%2Bsqrt%28+1040+%29%29%2F2%5C7+=+3.44635935665673\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-16%29-sqrt%28+1040+%29%29%2F2%5C7+=+-1.16064507094244\"
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\n" ); document.write( " Quadratic expression \"7x%5E2%2B-16x%2B-28\" can be factored:
\n" ); document.write( " \"7x%5E2%2B-16x%2B-28+=+7%28x-3.44635935665673%29%2A%28x--1.16064507094244%29\"
\n" ); document.write( " Again, the answer is: 3.44635935665673, -1.16064507094244.\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%2B-16%2Ax%2B-28+%29\"
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