Question

In triangleABC,Bcis equal to AB and Bus 80 then A
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Answer 1

Answer:

Given that in triangle ABC, BC = AB which means ABC is an isosceles triangle.

We know the sum of angles in a triangle is 180°. Since it is an isosceles triangle the measure of two angles will be same. Let ∠A = x and ∠c = x

We know,

Sum of all angles = 180°

x+x+80° = 180°

2x= 180°-80°

2x=100°

x=  = 50

Thus the measure of ∠A = 50°

Step-by-step explanation:

Answer 2

Answer: 50°

Step-by-step explanation: because in a isosceles triangle ABC AB=CB(given)

Then, <A=<C( angle opposite to the equal sides of a triangle is equal). By the angle sum property of a triangle <A+<B+<C=180° since <A=<C we can write <A+<A+<B=180°

2<A+<B=180°

2<A+80°=180°

2<A=180°-80°

<A=100°/2

Therefore, <A=50°