Question

1. Розв'яжи рiвняння. a) (4x-40) - (2x + 60) = -100;
б)-9*(х+1)+(-11х+19)=0
в)х+2/2-3х+4/12=3х+2/3
Допоможіть даю 50 балів​

Answer 1

a)

$(4x - 40) - (2x + 60) = - 100 \\ 4x - 40 - 2x - 60 = - 100 \\ 2x = - 100 + 100 \\ 2x = 0 \\ x = 0$

б)

$- 9(x + 1) + ( - 11x + 19) = 0 \\ - 9x - 9 - 11x + 19 = 0 \\ - 20x + 10 = 0 \\ - 20x = - 10 \\ x = - 10 \div ( - 20) \\ x = 0.5$

в)

$\frac{x + 2}{2} - \frac{3x + 4}{12} = \frac{3x + 2}{3} \: \: | \times 12\\ 6(x + 2) - (3x + 4) = 4(3x + 2) \\ 6x + 12 - 3x - 4 = 12x + 8 \\ 3x + 8 = 12x + 8 \\ 3x - 12x = 8 - 8 \\ - 9x = 0 \\ x = 0$