BA=5√3, угол А=30 градусов. Найти ВС​

5 + 3 * х - 8/2 + 6 - х/3 = 4
5 + 3х - 4 + 6 - 1/3х = 4
3х - 1/3х = 4 - 5 + 4 - 6
2 2/3х = - 3
х = - 3 : 2 2/3 = - 3 : 8/3 = - 3 * 3/8 = - 9/8 = - 1 1/8
х = - 1 1/8
Проверка: 5 + 3 * (- 9/8) - 4 + 6 - (- 9/8 : 3) = 5 - 27/8 - 4 + 6 + 3/8 = 5 - 27/8 + 3/8 - 4 + 6 = 5 - 24/8 - 4 + 6 = 5 - 3 - 4 + 6 = 4

3 * х - 5/5 + 18 + х/6 = 25
3х - 1 + 18 + 1/6х = 25
3х + 1/6х = 25 + 1 - 18
3 1/6х = 8
х = 8 : 3 1/6 = 8 : 19/6 = 8 * 6/19 = 48/19 = 2 10/19
х = 2 10/19
Проверка: 3 * 48/19 - 1 + 18 + 48/19 : 6 = 144/19 + 17 + 8/19 = 7 11/19 + 8/19 + 17 = 8 + 17 = 25