Find the measure of angle C of a triangle ABC, if m∠A = α, m∠B = 2α

The measure of angle C is 180 - 3α

Step-by-step explanation:

Given;

triangle ABC, ΔABC

angle A, ∠A  = α

angle B, ∠B = 2α

To calculate angle C, we must recall that, the sum of angles in a triangle is equal to  180°. Angle A, angle B, and angle C make up the total angle in the triangle.

∠A + ∠B  + ∠C = 180

where

∠C  is angle C

α + 2α + ∠C = 180

3α  + ∠C  = 180

∠C = 180 - 3α

∠C = 3(60 - α)

Therefore, the measure of angle C is 180 - 3α

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1

i just took the test, the correct answer is .. 31.5 in.