X^2-4=(x-2)(x+2);
25-9a^2=(5-3a)(5+3a);
36m^2-100n^2=(6m-10n)(6m+10n);
0,04p^2-1.69q^2=(0,2p-1,3q)(0,2p+1,3q);
x^2y^2-4/9=(xy-2/3)(xy+2/3);
a^4-b^6=(a^2-b^2)(a^2+b^2)b^2;
0.01c^2-d^8=(0.1c-2d)(0,1c+2d)4d;
0,81y^10-400z^12=(0,9y^5-20z^6)(0.9y^2+20z^2);
-1+49a^4b^8=-(1+7a^2b^4)(1-7a^2b^2);
1(7/9)m^2n^2-1(11/25)a^6b^2=)3/4ab-6/5a^3b)(3/a4ab+6/5^3b);