2. Prove that each angle of an equilateral trias
60°. Hence show that every equilateral triang
is equiangular. What is the measure of each of
exterior angle of an equilateral triangle?
ionale
Answers
Answer:
.As we know that all sides of a equilateral triangle are equal therefore
Step-by-step explanation:
In triangle ABC
AB=BC=AC
then angle C= angle A = angle B. (angle opposite to equal sides are also equal)
then,In triangle ABC
AngleA + AngleB +Angle C = 180 (Angle sum property of triangle)
3 Angle A= 180
Angle A= 60
As Angle A= angle B = angle C =60
Hence each angle is 60 and every equilateral triangle is equiangular.
Each exterior angle measures 120.
Solutions:
Let △ABC be an equilateral triangle. Then, AB = BC = CA.
Since, angles opposite to equal sides of a triangle are equal.
Hence, AB = BC and BC = CA
=> ∠C = ∠A and ∠A = ∠B
=> ∠A = ∠B = ∠C ............... (i)
Using angle sum property in△ABC, we obtain
∠A + ∠B + ∠C = 180°
=> ∠A + ∠A + ∠A = 180° .....[Using (i)]
=> 3∠A = 180°
=> ∠A = 60°
Hence, ∠A = ∠B = ∠C = 60°