№1
а) 30a^2 + 11ab = a(30a+11b);
б) 17m^5-5m^2 = m(17m^4 - 5m);
в) 12z^2y^4 - 18x^3y^3 + 6x^2y = y(12z^2y^3 - 18x^3y^2 + 6x^2);
№2
a) 4c(a-c)+7c(a-c) = (a-c)(4c+7c);
б) xz + yz + 5x+ 5y = z(x+y)+5(x+y) = (x+y)(z+5)
№3
а) 5a^2 - 45b^4 = 5(a^2 - 9b^4);
б) -4m^2 + 24mn - 36n^2 = 4(-m^2 + 6mn - 9n^2);
№4
x^3 + 5x^2 - 25x - 125 = 0
x^2(x+5)-25(x+5) = 0
(x+5)(x^2 - 25) = 0
(x+5)(x-5)(x+5) = 0
x+5=0 или x-5=0
x=-5 x=5
Ответ: x=-5; x=5