document.write( "Question 701104: How do I solve this set of simulataneous equation?
\n" ); document.write( "xy+20=5x
\n" ); document.write( "x-2y-3=0 \n" ); document.write( "
Algebra.Com's Answer #432222 by DrBeeee(684)\"\" \"About 
You can put this solution on YOUR website!
Normally you can't because of the nonlinear term x*y, but in this case you can get the solution by substitution.
\n" ); document.write( "Given
\n" ); document.write( "(1) xy + 20 = 5x and
\n" ); document.write( "(2) x - 2y -3 = 0
\n" ); document.write( "Solve (2) for y
\n" ); document.write( "yields
\n" ); document.write( "(3) y = (x-3)/2
\n" ); document.write( "Put this y into (1) and get
\n" ); document.write( "(4) x(x-3)/2 + 20 = 5x or
\n" ); document.write( "(5) x^2 - 3x + 40 = 10x or
\n" ); document.write( "(6) x^2 - 13x + 40 = 0
\n" ); document.write( "which factors to
\n" ); document.write( "(7) (x-5)*(x-8) = 0
\n" ); document.write( "which has roots for x
\n" ); document.write( "(8) x = {5,8}
\n" ); document.write( "Put each value of x into (2) and get the corresponding values of y
\n" ); document.write( "(9) y = {1,5/2} or the solution points
\n" ); document.write( "(10) (5,1) and (8,5/2)
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