Factorising the Difference of Two Squares

Question 1:

x2 36
x + 6 x 6

Question 1:

x2 9
x + 3 x 3

Question 1:

x2 169
x + 13 x 13

Question 1:

x2 1
x + 1 x 1

Question 1:

9 x2 1
3 x + 1 3 x 1

Question 1:

16 x2 25
4 x + 5 4 x 5