Answer:
19 seconds
Step-by-step explanation:
the amount of seconds on the graph are counted by two, right? so all you gotta do is count by twos on the horizontal lines until you reach the bottom of the curve again.
one solution x = 11/7 hope this can help you!
mcccccccccccccccccccccccccccccccccccccccccccccc
3p + 7q = 55
7p + 7q = 91
(-)
-4p=-36
p=9
q=4