Question

Give this Answer Urgently.​

Answer 1

Step-by-step explanation:

12) let say interior angles are x,y and z

so x+y+z=180. ----eq1

the exterior angle of x is 180 -x

and same way y is 180-y

and z is 180-z

so add all of them

180-x+180-y+180-z = 540-(x+y+z)

= 540-180(from 1)

= 360

hence proved

13)

c =p since PQ!! ST

so c=20

same way angle a = angle b

we know that c+30+b=180

20+30+b=180

b=180-50=130

so a=b=130 (corresponding angels)

14)

given A =B+C

we know that A+B+C =180

A+(B+C)=180

A+A =180

2A=180

A=180/2

A=90