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
\n" ); document.write( "\n" ); document.write( "Solve each of the following systems.
\n" ); document.write( "(1) x + y = 5
\n" ); document.write( " x^2 + y = 5\r
\n" ); document.write( "\n" ); document.write( "(2) x - y = 2
\n" ); document.write( " x^2 + y^2 = 4\r
\n" ); document.write( "\n" ); document.write( "(3) x^2 + y^2 = 12
\n" ); document.write( " x^2 + y = 10\r
\n" ); document.write( "\n" ); document.write( "(4) x^3 - 2^x - 5X + 6 = 0
\n" ); document.write( " 3x - y + 6 = 0
\n" ); document.write( "

Algebra.Com's Answer #42802 by Nate(3500)\"\" \"About 
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( "\"graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C5+-+x%2C5+-+x%5E2%29\"
\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( "\"graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C3x+%2B+6%2Cx%5E3+-+x%5E2+-+5x+%2B+6%29\"
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