11+3 х=55+4 х

-15-4 х--8+45

-8 х-17=3 х-105

2 (y+3) = 21-3y

(2-c) + 3 (c-3) = - 13

-3 (l-3b) - 12=12

1. 11+3 х=55+4 х

3x-4x=55-11

-x=44

x=-44

2. - 15-4 х=-8+45

-4x=-8+45+15

-4x=52

x=-13

3. - 8 х-17=3 х-105

3x+8x=17-105

11x=-88

x=-8

4. 2 (y+3) = 21-3y

2y+6=21-3y

2y+3y=21-6

5y=15

y=3

5. (2-c) + 3 (c-3) = - 13

2-c+3c-9=-13

2c=-13+9-2

2c=-6

c=-3

6. - 3 (l-3b) - 12=12

-3+9b-12=12

9b=12+12+3

9b=27

b=3