Question

this question urgent please​

Answer 1

Answer:

x = b + c - 2a

y = c + a - 2b

z = a + b - 2c

⇒ x + y + z = (b + c - 2a) + (c + a - 2b) + (a + b - 2c) = 0

Now,

⇒ x2 + y2 + 2xy - z2

⇒ (x + y)2 - z2 [∴ (a2 - b2) = (a + b) (a - b)]

⇒ (x + y - z) (x + y + z)

As we know, (x + y + z) = 0

∴ x2 + y2 - z2 + 2xy

= 0 × (x + y - z)

= 0

p.s the 2 after the numbers/letters represent the letters/numbers being squared :)