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In triangle ABC, measure of angle A is 70°. Angle B is congruent to angle C. What is the measure of angle B in degrees?

User Kgrover
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2 Answers

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Final answer:

In triangle ABC, angle B, which is congruent to angle C, has a measure of 55°.

Step-by-step explanation:

In triangle ABC, angle A is given as 70°. Angle B is congruent to angle C. To find the measure of angle B, we can use the fact that the sum of the angles in a triangle is always 180°.

Since angle B and angle C are congruent, they have the same measure. Let's assume their measure to be x. Now, we can set up the equation:

70° + x + x = 180°

Combining like terms, we get:

70° + 2x = 180°

Subtracting 70° from both sides, we have:

2x = 110°

Finally, dividing both sides by 2, we find:

x = 55°

Therefore, the measure of angle B is 55°.

User Acrogenesis
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Since the sum of all three angles in a triangle is always 180°, you know the measure of angle A, and you know that the measures of B and C are equal, you can set up an equation like this:

180 = 2x + 70

Subtract 70 from both sides:

110 = 2x

Isolate x:

55 = x

So, the measure of angle B (and C) is 55°.

Hope this helped!! xx



User Serban Razvan
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