Question

Two angel of a triangle are equal and third angel is 80.find the measure of equal angel

Answer 1

Answer:

Consider ∠A and ∠B in a triangle is x

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We know that the sum of all the angles in a triangle is 180

∘

.

So we can write it as

∠A+∠B+∠C=180

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By substituting the values

x

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+x

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+∠C=180

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By addition

2x

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+∠C=180

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..(1)

According to the question we get

∠C=x

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+18

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.(2)

By substituting (2) in (1) we get

2x

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+x

∘

+18

∘

=180

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On further calculation

3x

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+18

∘

=180

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By subtraction

3x

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=180

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−18

∘

3x

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=162

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By division

x

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=162/3

x

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=54

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By substituting the values of x

∠A=∠B=54

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∠C=54

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+18

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=72

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Therefore, ∠A=54

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,∠B=54

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and ∠C=72

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