1) (x-y)(x+y2) (c-5)(c+53) (5-a)(5+a4) (m-n)(m+n5) (b-0.2)(b+0.26) (n-2/3)(n+2/37) (10-p)(10+p8) (a-1)(a+19) (7-b)(7+b10) (m-20)(m+2011) (1.1-x)(1.1+x12) (5/8-p)(5/8+p)
1) (x-y)(x+y
2) (c-5)(c+5
3) (5-a)(5+a
4) (m-n)(m+n
5) (b-0.2)(b+0.2
6) (n-2/3)(n+2/3
7) (10-p)(10+p
8) (a-1)(a+1
9) (7-b)(7+b
10) (m-20)(m+20
11) (1.1-x)(1.1+x
12) (5/8-p)(5/8+p)