Решите уравнения:

1) - 3 х=2 1/7

2) 3/4 х=1/2

3) 7 х+8=11

4) 4 х+4=х+5

5) 8 у-9 - (4 у-5) = 12 у - (4+5 у)

6) 5 (8z-1) - 7 (4z+1) + 8 (7-4z) = 25

7) x/3+x/5=8

1) - 3x = 15/7

x = 15/7 : (-3/1)

x = 15/7 * (-1/3)

x = - 5/7

2) x = 1/2 : 3/4

x = 1/2 * 4/3

x = 2/3

3) 7x=11-8

7x=3

x=3/7

4) 4x-x=5-4

3x=1

x=1/3

5) 8y-9-4y+5=12y-4-5y

8y-4y-12y+5y=-4+9-5

-3y=0

y=0 : - 3

y=0

6) 40z-5-28z-7+56-32z=25

40x-28z-32z=25+5+7-56

-20z=-19

z=19/20

7) 5x+3x=10

8x=120

x=120/8

x=15