Answer:
B = 25
Step-by-step explanation:
x/100×8.5=2.1
8.5x/100=2.1
8.5x=100×2.1
8.5x=210
8.5x/8.5=210/8.5
x=24.70
x=25
to know the summation of angles: (n-2)*180
here (n) represent numbers of sides
12)we have 5 sides (n=5)
(5-2)*180=540
x=540-(105+135+92+87)=121
13)we have 8 sides (n=8)
(8-2)*180=1080
x=1080-(116+158+141+124+136+132+129)=144
I hope it will help
DBE = 33
add 23 + 27 = 50
subtract 50 from 83
equals 33
