Question

( n^{2}+y^{2}+2 n y-z^{2} )
( =(n+y)^{2}-z^{2} )
( =(n+y+2)(n+y-2) )
( =5+(-2 a+c+a-2 b+a+b-2 c) times(n+y-2) )
( =(2 b-2 b+2 k-2 c+2 a-2 a) times(n+y-2) )
( =0 ) (A) ( frac{4 n c}{3} )

# If x = b + c-2a, y = c + a - 2b, z = a + b - 2c, then the value of x² + y2 - Z? + 2xy is: (A) 0 (B) a + b + c (C) a - b + c (D) a + b-C

Solution