Question

4х-5=0 решите уравнение
3х+0,4=2х+1,8
9х-(х-5)=8
11-3(х-1,5)=4-2х
0.3(х+1)-0.6(х-5)=0,5х-2​

Answer 1

Ответ:

$4x - 5 = 0 \\ 4x = 0 + 5 \\ 4x = 5 \\ x = 5 \div 4 \\ x = 1 \frac{1}{4}$

$3x + 0.4 = 2x + 1.8 \\ 3x + 0.4 - 2x - 1.8 = 0 \\ x - 1.4 = 0 \\ x = 0 + 1.4 \\ x = 1.4$

$9x - (x - 5) = 8 \\ 9x - x + 5 = 8 \\ 8x + 5 = 8 \\ 8x = 8 - 5 \\ 8x = 3 \\ x = 3 \div 8 \\ x = \frac{3}{8}$

$11 - 3(x - 1.5) = 4 - 2x \\ 11 - 3x + 4.5 = 4 - 2x \\ 15.5 - 3x = 4 - 2x \\ 15.5 - 3x - 4 + 2x = 0 \\ - x + 11.5 = 0 \\ - x = 0 - 11.5 \\ - x = - 11.5 \\ x = 11.5$

$0.3(x + 1) - 0.6(x - 5) = 0.5x - 2 \\ 0.3x + 0.3 - 0.6x + 3 = 0.5x - 2 \\ - 0.3x + 3.3 = 0.5x - 2 \\ - 0.3x + 3.3 - 0.5x + 2 = 0 \\ - 0.8x + 5.3 = 0 \\ - 0.8x = 0 - 5.3 \\ - 0.8x = - 5.3 \\ x = - 5.3 \div ( - 0.8) \\ x = 53 \div 8 \\ x = 6 \frac{5}{8}$