document.write( "Question 624570: Does anyone know how to do this i need help. \r
\n" ); document.write( "\n" ); document.write( "Use the substitution method to solve the system
\n" ); document.write( "x^2+y^=20
\n" ); document.write( "x+y=1 \n" ); document.write( "

Algebra.Com's Answer #392868 by oscargut(2103) $\"\"$ $\"About$

You can put this solution on YOUR website!
x^2+y^2=20
\n" ); document.write( "x+y=1\r
\n" ); document.write( "\n" ); document.write( "Solution:\r
\n" ); document.write( "\n" ); document.write( "y = 1-x\r
\n" ); document.write( "\n" ); document.write( "x^2+(1-x)^2=20\r
\n" ); document.write( "\n" ); document.write( "2x^2-2x+1 = 20\r
\n" ); document.write( "\n" ); document.write( "2x^2-2x-19 = 0\r
\n" ); document.write( "\n" ); document.write( " $\"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%2A2%2A%28-19%29+%29%29%2F%282%2A2%29+\"$
\n" ); document.write( " $\"x+=+%282+%2B-+2%2Asqrt%28+39+%29%29%2F4+\"$
\n" ); document.write( " $\"x+=+%281+%2B-+sqrt%28+39+%29%29%2F2+\"$ \r
\n" ); document.write( "\n" ); document.write( "if $\"x+=+%281+%2B+sqrt%28+39+%29%29%2F2+\"$ then $\"y+=+%281+-+sqrt%28+39+%29%29%2F2+\"$
\n" ); document.write( "if $\"x+=+%281+-+sqrt%28+39+%29%29%2F2+\"$ then $\"y+=+%281+%2B+sqrt%28+39+%29%29%2F2+\"$ \r
\n" ); document.write( "\n" ); document.write( "Solutions:\r
\n" ); document.write( "\n" ); document.write( " $\"x+=+%281+%2B+sqrt%28+39+%29%29%2F2+\"$ , $\"y+=+%281+-+sqrt%28+39+%29%29%2F2+\"$
\n" ); document.write( " $\"x+=+%281+-+sqrt%28+39+%29%29%2F2+\"$ , $\"y+=+%281+%2B+sqrt%28+39+%29%29%2F2+\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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