Respuesta :

Answer/Step-by-step explanation:

Given:

C = right angle = 90°

BC = a = ?

AB = c = 12

AC = b = 9

Required:

a, <A, and <B

Solution:

✔️Find a using Pythagorean Theorem:

a = √(c² - b²)

a = √12² - 9²) = √63

a = 7.93725393 = 8 (nearest whole number)

✔️Find A by applying trigonometric ratio:

Thus,

Reference angle = A

Hypotenuse = 12

Adjacent = 9

Therefore,

[tex] cos(A) = \frac{adj}{hyp} = \frac{9}{12} [/tex]

[tex] cos(A) = 0.75 [/tex]

[tex] A = cos^{-1}(0.75) [/tex]

m<A = 41° (nearest whole number)

✔️Find B:

m<B = 180 - (90 + 41) (sum of interior angles of triangle)

m<B = 49°