Question

(3a+b) (3a-b)=------- ?

Answer 1

Answer:

3a²-b²

Step-by-step explanation:

(a+b)*(a-b) is always of the form a²-b²

here a is 3a and b is b

so 3a²-b². you cant simplify more.

Answer 2

Answer:

9a^2-b^2

Step-by-step explanation:

1) distribute:- (3a+b) (3a-b)

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

                     =9a^2-3ab+3ab-b^2

                       (-3ab and +3ab are canceled)

                     =9a^2 - b^2