3. Решите уравнения, учитывая скобки a) 6(x-2)-x = 13 b) 3x + 2(2x-7)=35 c) 0,2(5x + 10) = 7

a) 6x - 12 - x = 13; 5x = 13 + 12; 5x = 25; x = 5.
b) 3x + 4x - 14 = 35; 7x = 35 + 14; 7x = 49; x = 7.
c) x + 2 = 7; x = 7 - 2; x = 5.