2x+2y=8.......(i) x^2+y^2=26..(ii)

2x+2y=8 --> x+y=4 --> x=4-y
x^2+y^2=26
(4-y)^2+y^2=26
16-8y+y^2+y^2=26
16-8y+2y^2=26
y^2-4y+8=13
y^2-4y+8-13=0
y^2-4y-5=0
(y-5)(y+1)=0
y-5=0 atau y+1=0
y=5 atau y=-1

y=5 --> x=4-y=4-5=-1 atau
y=-1 --> x=4-y=4-(-1)=5