Y*60=5620-4120
y*60=1500
y=1500:60
y=25
d*60=5600-4160
d*60=1440
d=1440:60
d=24
cos a=A/E E=f*S=90*180=16200 cos a=8=100/16200=0.5 a=60гр
1*12/11*12+1*11/11*12+1/13+1/14+1/14
23/132+1/13+1/14+1/14
23*13/132*13+1*132/13*132+1/14+1/14
431/1716+1/14+1/14
(1/14+1/14=2/14=1/7)
431/1716+1/7=431*7/1716*7+1*1716/7*1716=4733/12012
4733/12012>1/3
37740:5:4=1887
37740:5=7548
7548:4=1887