Question

Q. Find the lettered angle in each case :- Solve the Solution.

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Answer 1

Answer:

• Value of a is 85°.

Step-by-step explanation:

To find :-

• Value of a.

Solution :-

❖ By first method :

Sum of all interior angles of triangle is equal to 180°.

So,

⇒∠1 + 35° + 50° = 180°

⇒∠1 + 85° = 180°

⇒∠1 = 180° - 85°

⇒∠1 = 95°

We know,

Sum of all angles forms on straight line is 180°. This statement is also known as 'linear pair'.

So,

⇒∠1 + a = 180°

⇒95° + a = 180°

⇒a = 180° - 95°

⇒a = 85°

Thus,

Value of a is 85°.

❖ By second method :-

We know,

Sum of any two interior angles of triangle is equal to one opposite exterior angle.

So,

⇒a = 35° + 50°

⇒a = 85°

Thus,

Value of a is 85°.