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What is the missing angle

What is the missing angle-example-1
User Defmeta
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2 Answers

17 votes
17 votes


Answer ☘️

Important points to know


{\boxed{ \bold{Exterior \: Angle \: Theorem : - }}}

  • The exterior angle of a triangle is equal to the sum of the two opposite interior angles.

  • \pink{ ↪ \sf \angle \: C + \angle \: D = \angle \: B}

Let's solve :-


\sf ↪\angle \: 65 \degree + \angle \: 30 \degree =\angle \:B\\ \\ \sf ↪\angle \: 95 \degree = \angle \:B

Hence option A 95⁰ is the right ans ✓


\sf{\:мѕнαcкεя\: ♪...}

User JSNinja
by
2.6k points
11 votes
11 votes


\sf\large \green{\underbrace{\red{Answer⋆}}}:

To find :-

The angle ∠ABC = ?

Given :-

∠BCD = 65°

∠BDC = 30°

Solution :-

Firstly we have to find ∠CBD, with the help of ∠CBD, we will able to find ∠ABC.

To find ∠CBD, we will use angle sum formula

(=> The sum of angles of all 3 sides of triangle is equal to 180°).

∠CBD + ∠BCD + ∠BDC = 180° (angle sum property)

∠CBD + 65° + 30° = 180°

∠CBD + 95° = 180°

∠CBD = 180° - 95°

∠CBD = 85°

Now we have ∠CBD, and in the diagram ∠CBD and ∠ABD lies on the same line but it is seperated by line BC, it means they are linear pair and the sum of both angles (∠CBD and ∠ABC) is equal to 180°.

∠ABC + ∠CBD = 180° (linear pair)

∠ABC + 85° = 180°

∠ABC = 180° - 85°

∠ABC = 95°

Result :-

The ∠ABC is 95° by using the above method.

Choose the first option

(A) 95°

User Konr Ness
by
3.0k points