Himpunan penyelesaian dari sistem x + y = 1 danx2+ y2 = 25

X+y = 1
x = 1-y

x^2+y^2 = 25
(1-y)^2+y^2 = 25
1-2y+y^2+y^2 = 25
2y^2-2y+1-25 = 0
2y^2-2y-24 = 0 (bagi 2 kedua ruas)
y^2-y-12 = 0
(y-4)(y+3) = 0
y = 4 atau y = -3

Jika y = 4:
x = 1-y
x = 1-4
x = -3

Jika y = -3:
x = 1-y
x = 1-(-3)
x = 4

HP = {(-3,4),(4-3)}