Question

factorise: ax^2 + y^2 + z^2 - 6xy + 2yz - 6xz hence find its value if x = 1, y = 2 and z = -1.

Answer 1

Step-by-step explanation: Hey mate, here you go

(a×1²)+(2²)+ (-1)²+(-6×1×2)+(+2×2×-1 )+(-6×1×-1)

=a+4+1-12-4+6

= -5+a

a=+5

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