Question

Solve the system:

x^2+y^2=5
x+y=3

Answer 1

x=1 y=2

Answer 2

express y in terms of x from 2º equation:
y=3-x
substitute in the 1º:
x^2+(3-x)^2=5
solve: x^2+9-6x+x^2=5
2x^2-6x+4=0
x^2-3x+2=0
(x-2)(x-1)=0 so two posible values for x
x=1, and x=2
if x=1
y=2
if x=2 y=1