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in triangle ABC below the measure of angle a is 20 degrees in the measure of angle B is three times larger than a measure of angle C what is the measure of angle B?​

User CrazyElf
by
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1 Answer

3 votes

Answer:

In triangle ABC,

What are the angles?

the angles are A, B and C

What is the sum of all three angles in a triangle?

A + B + C = 180°

the measure of angle B is three times that of angle A.

What is angle B equal to, mathematically?

B is equal to 3A

the angles are now A, 3A and C

The measure of angle C is 20 degrees more than that of angle A.

What is angle C equal to, algebraically?

C is equal to A+20

the angles are now A, 3A, and A+20

How do you find the angle measures?

What is the sum of all angles in a triangle?

A + B + C = 180°

Write it again, this time with B = 3A, and C = A+20

A + (3A) + (A+20) = 180°

Simplify:

A + 3A + A + 20 = 180°

5A + 20 = 180°

Solve for A and you have angle A, then reread the above to get B and C.

I’m going to let you finish it from here.

What did you get?

Be sure you double check your answer.

Do your three angles add up to 180?

Is B triple the value of A?

Is C 20 more than A?

Explanation:

hopefully this helps

User Martin Kleppmann
by
4.9k points
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