Answer: (y^2-a)(1+x-b)
Explanation:
Factor out the common terms: =x(y^2-a)-by^2+ab+y^2-a
Then rewrite as: =(y^2-a)x-by^2+ab+1 x (y^2-a)
Factor out the common term (y^2 - a): =(y^2-a)(x+1)-by^2+ab
Factor out the common term b: =(y^2-a)(1+x)+b(-y^2+a)
Rewrite as: =(y^2-a)(1+x)-(y^2-a)b
Factor out the common term (y^2 - a): =(y^2-a)(1+x-b)