In isosceles triangle ABC, B is the vertex. The measure of angle B can be represented as (4x-2). The measure of angle A can be represented as (8x+1). Find the measure of all three angles of the triangle?

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Answer 1 · 2018-05-16T22:49:36

#m/_A = 73#, #m/_B = 34#, #m/_C = 73#.

Since #DeltaABC# is an isosceles triangle, angle A is congruent to angle C.

Knowing this, and the fact that a triangle's angle measures add up to 180, we can state:

#4x - 2 + 2(8x + 1) = 180#

Now solve for x.

#4x - 2 + 16x + 2 = 180#

#20x = 180#

#x = 9#

Now apply x to the two given angle measures to find the new measurements.

#4 * 9 - 2 = 34#

#8 * 9 + 1 = 73#

#m/_A = 73#, #m/_B = 34#, #m/_C = 73#.