(2 ц 7/9 z + 3 ц 1/3) *3/5=1/6z +6 ц 1/2
(25/9z+10/3)*3|5=1/6z+ 6ц 1/2
5/3z+2=1/6z+6ц1/2
5\3z-1/6z=4ц1/2
9/6z=9/2
z=9/2: 9/6
z=3
