Step-by-step explanation:

1. (b+7)(b-7)
2. (c+5)(c-5)
3. (d+4)(d-4)
4. (x+6)(x-6)
5. (y+9)(y-9)
6. 5(y²+2)

Answer:

1. (b - 7) (b + 7)

2. (c - 5) ( c + 5)

3. (d - 4) (d + 4)

4. (x - 6) (x + 6)

5. (y -9) (y + 9)

6. 5 (y^2 +2)