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2 votes
NEED HELP W GEOMETRY

In △
ABC, ∡A
is 2 more than twice ∡B
, and ∡C
is 7 less than twice ∡B
. What is the measure of each angle in △
ABC and what is its classifications?

User Ahmar
by
3.4k points

1 Answer

11 votes

Answers:

  • Angle A = 76
  • Angle B = 37
  • Angle C = 67

Triangle ABC is an acute triangle. It's also a scalene triangle.

====================================================

Work Shown:

x = measure of angle B

2x+2 = measure of angle A, since we're told its "2 more than twice angle B"

2x-7 = measure of angle C, for similar reasoning

The three angles add to 180. This is true for any triangle

A+B+C = 180

(2x+2)+(x)+(2x-7) = 180

5x-5 = 180

5x = 180+5

5x = 185

x = 185/5

x = 37

This means angle B is 37 degrees. The other two angles are

A = 2x+2 = 2*37+2 = 74+2 = 76

C = 2x-7 = 2*37-7 = 74-7 = 67

----------------

In summary, we have these three interior angles

  • A = 76
  • B = 37
  • C = 67

As a way to check, note how A+B+C = 76+37+67 = 180. This confirms the answer. All three angles mentioned are smaller than 90 degrees, so this triangle is acute.

Furthermore, because all three angles are different measures, this means all three sides are different lengths. This leads to triangle ABC being scalene.

User Kchromik
by
3.8k points