Question

(v) (x+y-z)2-(x-y+z)2​

Answer 1

Explanation:

2x+2y-2z+2x-2y+2z

cancel +2y -2y,-2z+ 2z

then left 2x+2x

2x+2x=4x

Answer 2

Correct Question:

Factorise : (x + y - z)² - (x - y + z)²

We know,

a² - b² = (a + b)(a - b)

So,

Consider,

• a = (x + y - z)
• b = (x - y + z)

(x + y - z)² - (x - y + z)²

= [(x + y - z) + (x - y + z)][(x + y - z) - (x - y + z)]

= (x + y - z + x - y + z)(x + y - z - x + y - z)

= (2x)(2y - 2z)