Question

Сколько будет 6×а+3×(18-а)=69?

Answer 1

$6 \times a + 3 \times (18 - a) = 69 \\ 6a + 54 - 3a = 69 \\ 3a + 54 = 69 \\ 3a = 69 - 54 \\ 3a = 15 \\ a = 5$

Answer 2

6*а+3*(18-а)=69

6а+54-3а=69

6а-3а=69-54

3а=15

а=5

Ответ: 5