document.write( "Question 62040: I tried to follow the directions on the video, but I got lost somewhere and messed up. I am lost.\r
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document.write( "Solve each of the following systems.
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document.write( "(1) x + y = 5
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document.write( " x^2 + y = 5\r
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document.write( "(2) x - y = 2
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document.write( " x^2 + y^2 = 4\r
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document.write( "(3) x^2 + y^2 = 12
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document.write( " x^2 + y = 10\r
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document.write( "(4) x^3 - 2^x - 5X + 6 = 0
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document.write( " 3x - y + 6 = 0 \n" );
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Algebra.Com's Answer #42802 by Nate(3500)![]() ![]() ![]() You can put this solution on YOUR website! (1) \n" ); document.write( "x + y = 5 is also ~> y = 5 - x \n" ); document.write( "x^2 + y = 5 \n" ); document.write( "x^2 + 5 - x = 5 Remember you can substitute the 5 - x in for y \n" ); document.write( "x^2 - x = 0 \n" ); document.write( "x(x - 1) = 0 \n" ); document.write( "x = 0 and x = 1 \n" ); document.write( "Plug: \n" ); document.write( "y = 5 - x \n" ); document.write( "(0,5) and (1,4) \n" ); document.write( " \n" ); document.write( "(2) \n" ); document.write( "x - y = 2 is also ~> x = 2 + y \n" ); document.write( "x^2 + y^2 = 4 \n" ); document.write( "(2 + y)^2 + y^2 = 4 \n" ); document.write( "4 + 4y + y^2 + y^2 = 4 \n" ); document.write( "2y^2 + 4y = 0 \n" ); document.write( "y^2 + 2y = 0 \n" ); document.write( "y(y + 2) = 0 \n" ); document.write( "y = 0 and y = -2 \n" ); document.write( "Plug: \n" ); document.write( "x = 2 + y \n" ); document.write( "(2,0) and (0,-2) \n" ); document.write( " \n" ); document.write( "(3) \n" ); document.write( "x^2 + y^2 = 12 is also ~> x^2 = 12 - y^2 \n" ); document.write( "x^2 + y = 10 \n" ); document.write( "12 - y^2 + y = 10 \n" ); document.write( "-y^2 + y + 2 = 0 \n" ); document.write( "(y + 1)(-y + 2) = 0 \n" ); document.write( "y = -1 and y = 2 \n" ); document.write( "Plug: \n" ); document.write( "x^2 = 12 - y^2 \n" ); document.write( "x = +- sqrt(12 - y^2) \n" ); document.write( "x = +- sqrt(12 - 1) = +- sqrt(11) \n" ); document.write( "(sqrt(11),-1) \n" ); document.write( "(-sqrt(11),-1) \n" ); document.write( "x = +- sqrt(12 - y^2) = +- sqrt(12 - 4) = +- sqrt(8) \n" ); document.write( "(sqrt(8),2) \n" ); document.write( "(-sqrt(8),2) \n" ); document.write( " \n" ); document.write( "(4) \n" ); document.write( "3x - y + 6 = 0 ~> red line demonstrates this line \n" ); document.write( "x^3 - x^2 - 5x + 6 = 0 ~> found from green line (x-intercepts are answers) \n" ); document.write( " |