Question

Please help on question 12 or 13 as soon as possible

Answer 1

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