Question

Factorise the following:

a(x² + y² – z²) – b(–x² – y² + z²)

Answer 1

Given expression: a(x² + y² – z²) – b(–x² – y² + z²)

Step 1: Remove the parentheses carefully and change signs in the second term:

a(x² + y² – z²) + b(x² + y² – z²)

Step 2: Notice both terms have the common factor (x² + y² – z²), so factor it out:

(x² + y² – z²)(a + b)