Question

i suck at math. △ABC△ABC is similar to △XYZ△XYZ by the ​ AA Similarity PostulateAA Similarity Postulate ​ . The measure of ∠A∠A is 39º and the measure of ∠C∠C is 24º. What is m∠Ym∠Y?

Answer 1

If △ABC is similar to △XYZ, the angles have the same degree measure.
Since m∠A is 39° and m∠C is 24°, and the total measure of the inner angles is;
(n - 2)180° = (3 - 2)180° = 180°,
180° = m∠A + m∠B + m∠C
180° = m∠B + 39° + 24°
m∠B = 117°
But because △ABC is similar to △XYZ, m∠B = m∠Y;
m∠B = m∠Y = 117°

Answer 2

180 degrees in a triangle. subtract the 2 know angles to get the third.
180-39-24=117