The Total solution for NCERT class 6-12
x2 – y2 – 4xz + 4z2= x2 – 4xz + 4z2 – y2= (x)2 – 2 x x x 2z + (2z)2 – (y)2= (x – 2z)2 – (y)2= (x – 2z + y) (x – 2z – y)= (x +y – 2z) (x – y – 2z)