Answer:
RS = 15 and RT = 18, then ST = 3! :D
Step-by-step explanation:r = 1 --> s=15 & t=18 so st = 270
r = 3 --> s = 5 & t = 6 so st = 30
r = 5 --> s = 3 & t = 3.6 so st = 10.8
etc
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In literal terms:
s = 15/r
t = 18/r
Hope this helped, I'm just in middle school but I'm sure of this! :D
