How can i find the value for R

Answer:
R = 134
Step-by-step explanation:
This is a 5 sided figure. The interior angles add to (n – 2)180 where n is the number of sides
(5-2) * 180 = 540
Add up all the angles and set it equal to 540
R+ 78+109+113+106 = 540
Combine like terms
R + 406 = 540
Subtract 406 from each side
R +406-406 = 540-406
R = 134