document.write( "Question 115723: Hi! I need help solving the following equation.
\n" ); document.write( "2x+y=10
\n" ); document.write( "x^2+y^2=25
\n" ); document.write( "Thanks so much \n" ); document.write( "
Algebra.Com's Answer #84364 by ankor@dixie-net.com(22740)\"\" \"About 
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2x + y = 10
\n" ); document.write( "x^2+y^2= 25
\n" ); document.write( ":
\n" ); document.write( "We are going to use the 1st equation for substituting in the 2nd equation:
\n" ); document.write( "2x + y = 10
\n" ); document.write( "y = (10-2x)
\n" ); document.write( ":
\n" ); document.write( "Substitute (10-2x) for y in the 2nd equation:
\n" ); document.write( "x^2 + (10-2x)^2 = 25
\n" ); document.write( ":
\n" ); document.write( "FOIL (10-2x)(10-2x); then we have:
\n" ); document.write( "x^2 + 100 - 40x + 4x^2 = 25
\n" ); document.write( ":
\n" ); document.write( "x^2 + 4x^2 - 40x + 100 - 25 = 0
\n" ); document.write( ":
\n" ); document.write( "5x^2 - 40x + 75 = 0
\n" ); document.write( ":
\n" ); document.write( "Simplify, divide equation by 5
\n" ); document.write( "x^2 - 8x + 15 = 0
\n" ); document.write( ":
\n" ); document.write( "Factor:
\n" ); document.write( "(x-5)(x-3) = 0
\n" ); document.write( ":
\n" ); document.write( "x = 5; and x = 3
\n" ); document.write( ":
\n" ); document.write( "Find y when x = 5:
\n" ); document.write( "y = 10 - 2x
\n" ); document.write( "y = 10 -2(5)
\n" ); document.write( "y = 0
\n" ); document.write( ":
\n" ); document.write( "Find y when x = 3
\n" ); document.write( "y = 10 - 2(3)
\n" ); document.write( "Y = 4
\n" ); document.write( ":
\n" ); document.write( "We have two sets of solutions:
\n" ); document.write( "x = 5; y = 0
\n" ); document.write( "and
\n" ); document.write( "x = 3; y = 4
\n" ); document.write( ":
\n" ); document.write( "You can confirm both of these solutions in both equations \n" ); document.write( "
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