Factorising quadratics

All questions please to be completed. I’m stuck.

1. (x +1)(x - 1)

2. (x+5)(x-5)

3. (x+12)(x-12)

4. (x+14)(x-14)

5. (x+5)(x-7)

Step-by-step explanation:

The first 4 expressions can be factored with the difference of squares type of factoring.

For #5, the odd one out is (x+5)(x-7) because it isn't a factor of any of the standard form equations, while the others are