Question 31753: Solve the system:
x^2+y^2=63
x^2-3y^2=27
a. (3 sqrt6,3) (3 sqrt6, -3)
b. (3 sqrt 6,3) (3 sqrt6,-3) (-3 sqrt6,3) (-3sqrt6,-3)
c. (1 sqrt62) (1,-62) (-1 sqrt62) (-1 -sqrt62)
d. (-3 sqrt6,3) (-3 sqrt6,-3)
Thanks a bunch!!!!!!!! Answer by mukhopadhyay(490) (Show Source):
You can put this solution on YOUR website! x^2+y^2=63...........(1)
x^2-3y^2=27 .........(2)
Subtracting (2) from (1) gives
4y^2 = 36
=> y^2 = 9
=> y=3 or y=-3
Using equation(1), If y=3 or -3, x^2 = 63-y^2 = 63-9 = 54
=> x=sqrt(54)or x=-sqrt(54)
=> x=3sqrt(6) or x=-3sqrt(6)
Correct option for the answer is b
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