SOLUTION: Find all pairs of real numbers (x,y) such that x + y = 6 and x^2 + y^2 = 28.

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Question 1074895: Find all pairs of real numbers (x,y) such that x + y = 6 and x^2 + y^2 = 28.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
This is a line interesting with a circle.
y=-x+6
x^2+x^2-12x+36=28
2x^2-12x+8=0
x^2-6x+4=0
x=(1/2)(6+/- sqrt (36-16); sqrt term is 2 sqrt (5)
x=3+/- sqrt (5)
numerically where x=5.24 and 0.76
where y=0.76 and 5.24.
Half circle shown below.
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2Csqrt%2828-x%5E2%29%2C-x%2B6%29
(5.24,0.76) and (0.76,5.24) numerically.