Answer:
[tex]\large\boxed{ax^2+ay^2-bx^2-by^2+b-a=(a-b)(x^2+y^2-1)}[/tex]
Step-by-step explanation:
[tex]ax^2+ay^2-bx^2-by^2+b-a\\\\=(ax^2-bx^2)+(ay^2-by^2)+(b-a)\qquad\text{use the distributive property}\\\\=x^2(a-b)+y^2(a-b)-1(a-b)\\\\=(a-b)(x^2+y^2-1)[/tex]
