Question 66228
x^2+y^2=36
2x^2-y^2=-9 now add these equations
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3x^2=27
x^2=27/3
x^2=9
x=+-3 substitute +-3 for x & solve for y
3*3+y^2=36
9+y^2=36
y^2=36-9
y^2=27
y=+-5.196