Question

Evaluate the given expression for:
x = -2, y = -1, z = 3.
$x^{2} + y^{2} + z^{2} - xy - yz - zx$

Answer 1

Step-by-step explanation:

= -2×-2+-1×-1+3×3+-2×-1--1×3-3×-2

= 4+1+9+2-3+6

= 20-3+1

= 21-3

= 18