SOLUTION: Please help solve this simultaneous equations x^2 = 4 - y x = y + 2 thanks AA

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Question 443408: Please help solve this simultaneous equations
x^2 = 4 - y
x = y + 2

thanks
AA

Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 = 4 - y
x = y + 2
then y = x-2 via the second equation... sub it back into the first.
x^2 = 4 - (x-2)
x^2 = 4 -x +2
x^2 = 6 -x
x^2 +x -6 = 0
(x+3)(x-2)
highlight%28x+=+-3%29 highlight%28x+=2%29
Plug each of these back in for x.
-3 = y +2
highlight%28-5+=+y%29
2 = y +2
highlight%280+=+y%29
So we have two solutions, (-3,-5) and (2,0).
Let's check each of these.
x^2 = 4-y
x = y + 2
9 = 4 +5 = 9 Check.
-3 = -5 + 2 = -3 Check.
So (-3,-5) works.
=============
Try (2,0)
4 = 4 - 0 = 4 Check.
2 = 0 +2 = 2 Check.
Both solutions work.
Again the solutions are
highlight%28x+=+-3+%29 highlight%28y+=+-5%29
highlight%28x+=+2%29 highlight%28y+=0%29