Question

ABCDE is a regular pentagon if angle abc is equal to 36 degree find angle 1 2 3​

Answer 1

Answer:

Step-by-step explanation:

we know that sum of angles A , B,C,D and E = 540 degree

there fore each angle A , B,C ,D and E measures = 108 degree

Angle A = 108 degree

now in triangle ABE ,

AB=AE ( because it is regular pentagon, all sides are equal)

so Triangle ABE is isosceles triangle.

Angle ABE = angle AEB                            (i)

now angle A + angle AEB+ angle AEB = 180

104 + 2 angle ABE= 180  (because of (i) )

angle AEB =36 degree (which is angle 2)

similarly angle 3 = 36 degree