Question

Find the measure of <_A. (show work if possible).

Answer 1

We know that exterior angle of a triangle is equal to the sum of two opposite interior angle.

Explanation:

<A = 4y

< B = 3y + 6°

<BCD = 111°

Now

<BCD = <A + <B( exterior angle of a triangle is equal to the sum of two opposite interior angle)

111° = 4y + 3y + 6°

111° - 6° = 7y

105° =7y

Therefore y = 15°

The measure of <A = 4*15°= 60°