document.write( "Question 613578: solve 2x^2-3x=7 using quadratic function and rounding to the nearest tenth \n" ); document.write( "
Algebra.Com's Answer #386080 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-3x%2B-7+=+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=%28-3%29%5E2-4%2A2%2A-7=65\".
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\n" ); document.write( " Discriminant d=65 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--3%2B-sqrt%28+65+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-3%29%2Bsqrt%28+65+%29%29%2F2%5C2+=+2.76556443707464\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-3%29-sqrt%28+65+%29%29%2F2%5C2+=+-1.26556443707464\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-3x%2B-7\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-3x%2B-7+=+%28x-2.76556443707464%29%2A%28x--1.26556443707464%29\"
\n" ); document.write( " Again, the answer is: 2.76556443707464, -1.26556443707464.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-3%2Ax%2B-7+%29\"
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