Factorising the Difference of Two Squares

Question 1:

x2 1
x + 1 x 1

Question 1:

x2 225
x + 15 x 15

Question 1:

x2 49
x + 7 x 7

Question 1:

x2 4
x + 2 x 2

Question 1:

4 x2 64
2 x + 8 2 x 8

Question 1:

25 x2 64
5 x + 8 5 x 8