x2 + y2 = 25 x + y = 7

x² + y² = 25
x+y = 7
x = 7-y

(7-y)² + y² = 25
49 - 14y + y² + y² = 25
2y² - 14y + 24 = 0
y² - 7y + 12 = 0
(y-3)(y-4) = 0
y - 3 = 0
y = 3
y - 4 = 0
y = 4

nilai x dan y yg memenuhi =
3 dan 4