Answer:
The solutions are (0, 4) and (0, -4)
Explanation:
Solve this system using substitution:
Take the negative of the first equation and add the result to the second one:
-x^2 + y^2 = 16 becomes x^2 - y^2 = -16
Then:
x^2 - y^2 = -16
-2x^2 + y^2 = 16
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-x^2 = 0, so x must be 0.
By the first equation, if x = 0, -(0)^2 + y^2 = 16, or
y^2 = 16, or y = ±4
The solutions are (0, 4) and (0, -4)