Answer:
m∠A = 106°
Step-by-step explanation:
All three sides of the triangle are given in the question.
To find the measure of included angle A between two sides we will apply cosine formula,
BC²= AB² + AC² - 2(AB)(AC)cosA
(13)² = (10)² + (6)² - 2(10)(6)cosA
169 = 100 + 36 - 120cosA
cosA = [tex]\frac{-169+136}{120}[/tex]
cosA = -0.275
A = [tex]\text{cos}^{-1}(-0.275)[/tex]
A = 105.96°
A ≈ 106°
Therefore, m∠A = 106° will be the answer.
