document.write( "Question 815416: 3x-4y=25
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Algebra.Com's Answer #490952 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
3x-4y=25
\n" ); document.write( "X^2-y^2=25
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\n" ); document.write( "3x-4y=25
\n" ); document.write( "y = (3x-25)/4
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\n" ); document.write( "X^2-y^2=25
\n" ); document.write( "\"x%5E2+-+%28%283x-25%29%2F4%29%5E2=25\"
\n" ); document.write( "\"16x%5E2+-+9x%5E2+%2B+150x+-+625+=+400\"
\n" ); document.write( "\"7x%5E2+%2B+150x+-+1025+=+0\"
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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 \"7x%5E2%2B150x%2B-1025+=+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=%28150%29%5E2-4%2A7%2A-1025=51200\".
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\n" ); document.write( " Discriminant d=51200 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-150%2B-sqrt%28+51200+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28150%29%2Bsqrt%28+51200+%29%29%2F2%5C7+=+5.44815499854966\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28150%29-sqrt%28+51200+%29%29%2F2%5C7+=+-26.8767264271211\"
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\n" ); document.write( " Quadratic expression \"7x%5E2%2B150x%2B-1025\" can be factored:
\n" ); document.write( " \"7x%5E2%2B150x%2B-1025+=+%28x-5.44815499854966%29%2A%28x--26.8767264271211%29\"
\n" ); document.write( " Again, the answer is: 5.44815499854966, -26.8767264271211.\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%2B150%2Ax%2B-1025+%29\"

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\n" ); document.write( "\"x+=+-75%2F7+%2B+80%2Asqrt%282%29%2F7\"\r
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\n" ); document.write( "\"x+=+-75%2F7+-+80%2Asqrt%282%29%2F7\"
\n" ); document.write( "Sub for x in the linear eqn and find y.
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