x = 600-20*ta)t-?,x = 300м,100м,20м,0м,-20мb)x-?,t = 10с,20с,0,5мин​

x=300

20t=600-300=300

t=300/20=15

x=100

20t=600-100=500

t=500/20=25

x=20

20t=600-20=580

t=580/20=29

x=0

20t=600

t=600/20=30

x=-20

20t=600+20

t=620/20=31

t=10

x=600-20*10=400

t=20

x=600-20*20=200

t=0,5мин=30сек

x=600-20*30=0