Question

in the given figure triangle ABC is an isosceles triangle in which ab is equal to AC and Angle A is equal to 50 degrees find the measure of Angle B and angle C

Answer 1

Angle c= angle b = 75

B=C(base angles of the isosceles triangle.)

AngleA + AngleB +AngleC =180

(Angle sum  property)

A=50

B=C (base angle of isosceles triangle)

So, 50+B+C=180

      50+B+B=180(B=C)

      50+2B=180

      2B=180-50

       B=130/2

        B= 65 = C

Answer 2

Step-by-step explanation:

ANSWER

Given, ABC is an isosceles triangle in which AB = AC

AEDC is a parallelogram

∠CDF=70

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and ∠BFE=100

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Since AEDC is a parallelogram

∠ACD+70

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=180

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⇒∠ACD=110

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→(1)

⇒∠ACD+∠GCB=180

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(∵ linear pair )

⇒∠GCB=180

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−110

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=70

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→(2)

∠GFD+∠BFE=180

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(linear pair)

⇒∠GFD=180

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−100

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=80

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→(3)

In ∠BFD,∠FBD=180

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−(80

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+70

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)=30

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SinceAB=AC,∠ABC=∠ACB

∴∠ABC=70

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⇒∠ABF=∠ABC−∠FBD=70

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−30

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=40

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