Пошаговое объяснение:

х + х - 30 + (х - 30) * 3 = 100

2х - 30 + 3х - 90 = 100

5х - 120 = 100

5х = 100 + 120

5х = 220

х = 220 : 5

х = 44

х + 30 = 44 + 30 = 74

х + 30 * 3 = 44 + 90 = 134

Ответ:

[tex]x + x - 30 + (x - 30) \times 3 = 100 \\ 2x - 30 + 3x - 90 = 100 \\ 5x - 120 = 100 \\ 5x = 120 + 100 \\ 5x = 220 \\ x = 220 \div 5 \\ x = 44[/tex]

[tex]x + 30 = 44 + 30 = 77[/tex]

[tex]x + 30 \times 3 = 44 + 30 \times 3 = 44 + 90 = 134[/tex]