Question

5.In ∆ABC, ∠A = 65⁰, ∠B = 45⁰, ∴ ∠C = ______ * *
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Answer 1

Given,

The value of ∠A = 65°

The value of ∠B = 45°

To find,

The value of ∠C.

Solution,

We can simply solve this mathematical problem by using the following mathematical process.

Now, we know that the sum of the three internal angles of a triangle is always 180°, we can use this property to derive the value of the third internal angle of the given triangle.

Let, the value of ∠C = x°

According to the data mentioned in the question,

65+45+x = 180

110+x = 180

x = 180-110

x = 70

Hence, the value of ∠C is 70°

Answer 2

Given:

In ∆ABC, ∠A = 65⁰, ∠B = 45⁰

To Find:

∠C of ∆ABC

Solution:

The Sum of all interior angles of a triangle is equal to 180° This property of triangles is known as 'angle sum property'.

We can find the third angle by this angle sum property.

⇒ ∠A + ∠B + ∠C = 180°

⇒ 65° + 45° + ∠C = 180°

⇒ 110° + ∠C = 180°

⇒ ∠C = 180° - 110°

⇒ ∠C = 70°

Hence ∠C is 70°