11. Реши уравнения

(x+3) * 5=725

4 949:7+x=20 678

2*x+908=4 052

5*b-1 209=1 256

1) (x + 3) * 5 = 725

x + 3 = 725/5

x + 3 = 145

x = 145 - 3 = 142

2) 4949 : 7 + x = 20678

707 + x = 20678

x = 20678 - 707

x = 19971

3) 2 * x + 908 = 4052

2 * x = 4052 - 908

2 * x = 3144

x = 3144/2 = 1572

4) 5 * b - 1209 = 1256

5 * b = 1256 + 1209

5 * b = 2465

b = 493

(x+3) * 5=275

5x+15=275

5x=275-15

5x=260

x=52

4949:7+x=20678

707+x=20678

x=20678-707

x=19971

2*x+908=4052

2x=4052-908

2x=3144

x=1572

5*b-1029=1256

5b=1256+1029

5b=2285

b=457