c = 8
Step-by-step explanation:
d=(r-c) t=?
20=(13-c)4=?
(13-c) * 4/ 4 =20/4
13-c=5
13-c-13=5-13
-c= -8
-c/-1 = -8/-1
answer is c=8
19.side- angle- side
20. angle- side- angle
step-by-step explanation: