Помогите решить уравнения на левой доске

2/15у + 3/4 = 5/6
2/15у = 5/6 - 3/4 
2/15у = 1/12
у = 1/12 * 15/12
у = 5/8

5/8m - 7/12m +5/6m = 1/4
21/24m = 1/4
m = 1/4 * 24/21
m = 6/21

2ц 1/15 - 3/4 m = 59/60
3/4m = 31|15 - 59|60
3/4m = 65/60
m =65/60 * 4/3 
m = 4 ц1/3