Math, asked by Islamkhan8908, 9 months ago

In a Δ ABC, if AB = AC and BC is produced to D such that ∠ACD =100°, then ∠A =
A. 20°
B. 40°
C. 60°
D. 80°

Answers

Answered by rushimane19
2

Answer:

Your answer is here A) 20

Answered by nikitasingh79
1

Given : In a Δ ABC, if AB = AC and BC is produced to D such that ∠ACD = 100°.

∠ACB + ∠ACD = 180°

[Linear pair]

∠ACB + 100° = 180°

∠ACB  = 180° - 100°

∠ACB  = 80°

∠ABC = ∠ACB = 80°  

[Angles opposite to equal sides are equal]

In ∆ABC,

We know that the sum of the angles of a triangle is 180°

∠A + ∠B + ∠C = 180°

∠A + 80° + 80° = 180°

∠A + 160°  = 180°

∠A  = 180° - 160°

∠A = 20°

Hence, ∠A is 20°.

Option (A) 20° is correct.

HOPE THIS ANSWER WILL HELP YOU…..

 

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