(a - b + 2)(a + b + 2)
3(4a+b+2c)
5ab-2ab+4a-b+5b = 3ab+4a+4b
(4a - 3b)(4a + 3b)
(ab/b) / (4a/5b) =(ab / b) * (5b / 4a) = (5ab2 / 4ab)= 5 / (4b)
n(2a - b)(2a + b)(4a^2 - 2ab + b^2)(4a^2 + 2ab + b^2)
(a - b + 2)(a + b + 2)
n(2a - b)(2a + b)(4a^2 - 2ab + b^2)(4a^2 + 2ab + b^2)
(a + 2 - b) (a + 2 + b)
3(4a+b+2c)
5(4a + 7)
5ab-2ab+4a-b+5b = 3ab+4a+4b
With the factor 4a plus 8b 16c you can find the answer and check it mentally. You would first have to find he product of all the numbers to find the value of the letter A.
Assuming the missing sign is "minus" then you have the difference between two squares. This is solved as (x + y)(x - y). In your example x = 4a and y = 2b so the factorisation is (4a + 2b)(4a - 2b) or more completely: (4)(2a + b)(2a - b).
(4a - 3b)(4a + 3b)
(ab/b) / (4a/5b) =(ab / b) * (5b / 4a) = (5ab2 / 4ab)= 5 / (4b)
They appear to be the equations of two parallel lines in the a-b plane.