Разложить на множители: 1)с^2-9 2); 25-n^2; 3)49m^-n^2; 4)d^2-16; 5)4c^-9; 6)25n^2-m^2 ; 7)49-m^2; 8) 9d^2-16

C^2-9=(c-3)(c+3)
25-n^2=(5-n)(5+n)
49m^2-n^2=(7m-n)(7m+n)
d^2-16=(d-4)(d+4)
4c^2-9=(2c-3)(2c+3)
25n^2-m^2=(5n-m)(5n+m)
49-m^2=(7-m)(7+m)
9d^2-16=(3d-4)(3d+4)

1) = (с+3)(с-3)
2) = (5-n)(5+n)
3) = (7m-n)(7m+n)
4) = (d-4)(d+4)
5) = (2c+3)(2c-3)
6) = (5n-m)(5n+m)
7) = (7+m)(7-m)
8) = (3d-4)(3d+4)