Question

In an isosceles triangle ABC, AB = AC and 2 A=30. . Find < B and C.​

Answer 1

Answer:

Given AB=AC

∠A=(2x+40)

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∠B=(4x+30)

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we have ∠B=∠C(∵AB=AC)

and sum of all the angles of a triangle=180

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∴∠A+∠B+∠C=180

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(2x+40)

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+(4x+30)

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+(4x+30)

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=180

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⇒10x+100

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=180

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⇒10x=80

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⇒x=8

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∴∠A=(2x+40)

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=(2×8+40)

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=56

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∠B=∠C=(4x+30)

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=(4×8+30)

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=62

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∠A=56

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∠B=62

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∠C=62

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Answer 2

Answer

Since one angle is given, (a = 30°), b = c as it is an isosceles triangle. In an isosceles triangle, two angles are equal. Since b = c, let us take its measure as x. Therefore the measure of angles b and c is 75°.