#### Answer

x=5
RM=11
ST=22

#### Work Step by Step

Since RM and RN are congruent with a 60 degree angle between them, SAS proves that it is an equilateral triangle. Therefore RM and RN are also congruent to MN.
RM=RN=MN=2x+1
ST=2(MN)
5x-3=4x+2
x=5
RM=2x+1
RM=2(5)+1
RM=11
ST=5x-3
ST=5(5)-3
ST=22