1) 3y^2(y^3 + 1) = 3y^5 + 3y^2
2) -9y(y - 3) + 4,5y(2y - 4) = -9y^2 + 27y +9y^2 - 18y = 9y
3) (x - 3)(x + 7) = x^2 - 3x + 7x - 21 = x^2 + 4x - 21
4) (3x + 2)(2x - 1) - (5x - 2)(x - 4) = 6x^2 + 4x - 3x - 2 - (5x^2 - 2x - 20x + 8) = 6x^2 + x - 2 - 5x^2 + 22x - 8 = x^2 + 23x - 10
5) 3mn - 4mk = m(3n - 4k)
6) m^2n + mn^2 = mn(m + n)
7) mn- mn^2 = mn(1 - n)
8) 2x^2 - 4x^6 = 2x^2(1 - 2x^3)
9) x^2 - 2x = 0
x (x - 2) = 0
x = 0 или x - 2 = 0
x = 2
Ответ: x = 0
x = 2
10) ax - ay + 5x - 5y = a(x - y) + 5(x - y) = (a + 5)(x - y)