решите уравнение 1)0,4(x-3)-1,6=5(0,1x-0,5) 2)1,5(2x-5)+2x=5(05x-1,5)-10 3)2/3(1...

Question

решите уравнение 1)0,4(x-3)-1,6=5(0,1x-0,5)
2)1,5(2x-5)+2x=5(05x-1,5)-10
3)2/3(1 1/2x+3/5)-4/5(5/12x-1/2)=1 3/5
помогите решить 6 класс

Answer 1

0.4 x - 1.2 - 1.6 = 0.5x - 2.5
0.4x - 0.5x = - 2.5 + 2.8
- 0.1 x = 0.3
x = -3


3x - 7.5 + 2x = 2.5 x - 7.5 - 10
3x - 2.5x +2x= -17.5 +7.5
2.5x = -10
x= - 10 : 2,5
х = -4


х +2/5 - 4/12 х + 4/10 = 8/5
8/12 х = 8/5 -2/5 -4/10
8/12 х = 8/10
х = 12/10 = 1  2/10 = 1 1/5