document.write( "Question 856323: 3rs-s^2=2 and 2r-3s=-4. Please solve and explain ,thanks \n" ); document.write( "
Algebra.Com's Answer #515932 by edjones(8007)\"\" \"About 
You can put this solution on YOUR website!
3rs-s^2=2
\n" ); document.write( "2r-3s=-4
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\n" ); document.write( "2r=3s-4
\n" ); document.write( "r=(3s-4)/2
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\n" ); document.write( "3s((3s-4)/2)-s^2=2
\n" ); document.write( "(9s^2-12s)/2-s^2=2
\n" ); document.write( "9s^2-12s-2s^2=4
\n" ); document.write( "7s^2-12s-4=0
\n" ); document.write( "s= -2/7, s=2 See below. I'll let you figure out r.
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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-12x%2B-4+=+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=%28-12%29%5E2-4%2A7%2A-4=256\".
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\n" ); document.write( " Discriminant d=256 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--12%2B-sqrt%28+256+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-12%29%2Bsqrt%28+256+%29%29%2F2%5C7+=+2\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-12%29-sqrt%28+256+%29%29%2F2%5C7+=+-0.285714285714286\"
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\n" ); document.write( " Quadratic expression \"7x%5E2%2B-12x%2B-4\" can be factored:
\n" ); document.write( " \"7x%5E2%2B-12x%2B-4+=+7%28x-2%29%2A%28x--0.285714285714286%29\"
\n" ); document.write( " Again, the answer is: 2, -0.285714285714286.\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-12%2Ax%2B-4+%29\"
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