Решите уравнения:

1) 3x-10.2=x

2) 3 (x-15) + 30 = 12x

3) 3x - (5-x) = 1

4) 5 (x-4.3) = 7 (x-0.5)

5) 0.4x - (0.2x-3.2) = 4.8

1) 3x-10.2=x

3x-x-10.2=0

2x=10.2

x=10.2 : 2

x=5.1

2) 3 (x-15) + 30=12x

3x-45+30=12x

-45+30=12x-3x

-15=9x

x=-15 : 9

x=-1⅔

3) 3x - (5-x) = 1

3x-5+x=1

3x+x=1+5

4x=6

x=6 : 4

x=1½

4) 5 (x-4.3) = 7 (x-0.5)

5x-21.5=7x-3.5

5x-7x=-3.5+21.5

-2x=18

x=18 : (-2)

x=-9

5) 0.4x - (0.2x-3.2) = 4.8

0.4x-0.2x+3.2=4.8

0.4x-0.2x=4.8-3.2

0.2x=1.6

x=1.6 : 0.2

x=8