document.write( "Question 348952: solve the following system of equations:\r
\n" ); document.write( "\n" ); document.write( "x + y + square root(xy) = 28
\n" ); document.write( "x^2 + y^2 + xy = 336
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Algebra.Com's Answer #249741 by ankor@dixie-net.com(22740)\"\" \"About 
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solve the following system of equations:
\n" ); document.write( "x + y + \"sqrt%28xy%29\" = 28
\n" ); document.write( "x^2 + y^2 + xy = 336
\n" ); document.write( ":
\n" ); document.write( "Simplify the 1st equation to use for elimination
\n" ); document.write( "x + y = \"28+-+sqrt%28xy%29\"
\n" ); document.write( "square both sides
\n" ); document.write( "\"x%5E2+%2B+2xy+%2B+y%5E2\" = \"784+-+56sqrt%28xy%29+%2B+xy\"
\n" ); document.write( "subtract xy from both sides
\n" ); document.write( "\"x%5E2+%2B+2xy+-+xy%2B+y%5E2\" = \"784+-+56sqrt%28xy%29\"
\n" ); document.write( "\"x%5E2+%2B+xy%2B+y%5E2\" = \"784+-+56sqrt%28xy%29\"
\n" ); document.write( ":
\n" ); document.write( "Use for elimination with 2nd equation
\n" ); document.write( "\"x%5E2+%2B+y%5E2%2B+xy\" = \"784+-+56sqrt%28xy%29\"
\n" ); document.write( "\"x%5E2+%2B+y%5E2+%2B+xy+=+336\"
\n" ); document.write( "---------------------------Subtraction eliminates everything on the left, we have:
\n" ); document.write( "\"0+=+448+-+56sqrt%28xy%29\"
\n" ); document.write( "\"56sqrt%28xy%29+=+448\"
\n" ); document.write( "divide both sides by 56, results:
\n" ); document.write( "\"sqrt%28xy%29+=+8\"
\n" ); document.write( "square both sides
\n" ); document.write( "xy = 64
\n" ); document.write( "y = \"64%2Fx\"
\n" ); document.write( ":
\n" ); document.write( "Substitute \"64%2Fx\" for y in the 1st equation
\n" ); document.write( "x + y + \"sqrt%28xy%29\" = 28
\n" ); document.write( "x + \"64%2Fx\" + \"sqrt%28x%2864%2Fx%29%29\" = 28
\n" ); document.write( "x's inside the radical cancel
\n" ); document.write( "x + \"64%2Fx\" + \"sqrt%2864%29%29\" = 28
\n" ); document.write( "x + \"64%2Fx\" + 8 = 28
\n" ); document.write( "x + \"64%2Fx\" = 28 - 8
\n" ); document.write( "x + \"64%2Fx\" = 20
\n" ); document.write( "multiply by x
\n" ); document.write( "x^2 + 64 = 20x
\n" ); document.write( "A quadratic equation
\n" ); document.write( "x^2 - 20x + 64 = 0
\n" ); document.write( "Factors to
\n" ); document.write( "(x-16)(x-4)
\n" ); document.write( "x = 16
\n" ); document.write( "x = 4
\n" ); document.write( ":
\n" ); document.write( "Find y:
\n" ); document.write( "When x=16: y = 64/16 = 4
\n" ); document.write( "When x=4: y = 64/4 = 16
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solution in the 1st equation
\n" ); document.write( "16 + 4 + \"sqrt%2816%2A4%29\" = 28
\n" ); document.write( "20 + \"sqrt%2864%29\" = 28; confirms our solutions; x=16, y-4 and x=4, y=16
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