x-15=5 10+x=55 123:50
100+556

1) Х - 15 = 5Х = 5 + 15Х = 202) 10 + Х  = 55Х = 55 - 10Х = 453) 123: 50 = 123 : (10 * 5) = 12,3 : 5 = 2,464) 100 + 556 = 656