Question

factorise X square + 4 y square minus z square - 4 x y

Answer 1

Answer

x²+4y²-z²-4xy

x²+4y²-4xy-z² (a²+b²-2ab=(a+b)²)

(x-2y)²-z² (a²-b²=(a+b)(a-b))

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