The figure is as shown above.
x1 + x2 = 2 × 3 = 6 …..(1)
x1 + x3 = 2 × 1 = 2 …..(2)
x2 + x3 = 2 × 5 = 10 …..(3)
Equation 1 – Equation 2 gives us
x2 – x3 = 4 …..(4)
Equation 3 + Equation 4,
2x2 = 14 ⇒ x2 = 7
∴ x1 = -1 and x3 = 3
Similarly,
y1 + y2 = 2 × -1 = -2 …..(5)
y1 + y3 = 2 × -3 = -6 …..(6)
y2 + y3 = 2 × 3 = 6 …..(7)
Equation 5 – Equation 6 gives us
y2 – y3 = 4 …..(8)
Equation 7 + Equation 8,
2y2 = 10 ⇒ y2 = 5
∴ y1 = -7 and y3 = 1
