Question

a²+ab-5a-5b=
a²-b²-a+b=
a²-b²+a+b=​

Answer 1

1) a² + ab - 5a - 5b = a(a + b) - 5(a + b) =

= (a + b)(a - 5)

2) a² - b² - a + b = (a - b)(a + b) - (a - b) =

= (a - b)(a + b - 1)

3) a² - b² + a + b = (a - b)(a + b) + (a + b) =

= (a + b)(a - b + 1)