17. Вычислите: 42⋅2−42, 4⋅15+15, 6⋅13−13

Решение:

• 42 ⋅ 2 - 42 = 84 - 42 = 42
• 4 ⋅ 15 + 15 = 60 + 15 = 75
• 6 ⋅ 13 - 13 = 78 - 13 = 65

Ответ: 42, 75, 65