Question

Розв'яжи рiвняння. a) x-5 = 1/2x + 1/2



ДАЮ 40 БАЛОВ ​

Answer 1

а)

$x - 5 = \frac{1}{2} x + \frac{1}{2} \\ x - \frac{1}{2} x = \frac{1}{2} + 5 \\ \frac{1}{2} = 5 \frac{1}{2} \\ x = 5 \frac{1}{2} \div \frac{1}{2} \\ x = \frac{11 \times 2}{2} \\ x = 11$

б)

$\frac{3x + 1}{4} - \frac{x}{6} = \frac{1 - x}{8} \: \: | \times 24 \\ 6(3x + 1) - 4x = 3(1 - x) \\ 18x + 6 - 4x = 3 - 3x \\ 14x + 3x = 3 - 6 \\ 17x = - 3 \\ x = - \frac{3}{17}$

в)

$\frac{2 - x}{5} + 2 = \frac{3 + 2x}{2} \: \: | \times 10 \\ 2(2 -x ) + 20 = 5(3 + 2x) \\ 4 - 2x + 20 = 15 + 10x \\ - 2x - 10x = 15 - 24 \\ - 12x = - 9 \\ x = \frac{3}{4} \\ x = 0.75$