Solve the simultaneously equation

X²+Y²=34
X+Y=2

1 answer

from x+y = 2
y = 2-x
sub into the other:
x^2 + (2-x)^2 = 34
x^2 + 4 - 4x + x^2 - 34 = 0
2x^2 - 4x - 30 = 0
x^2 - 2x - 15 = 0
(x - 5)(x + 3) = 0
x = 5 or x = -3

if x = 5, y = 2-5 = -3
if x = -3, x = 2 - (-3) = 5