Respuesta :

Answer:

1.28 or 912/715

Step-by-step explanation:

sine= opposite side/hypotenuse

cos=adjacent/ hypotenuse

sine a= 12/13 using the Pythagorean Theorem and solve for the missing side. (which is the adjacent side)

cos a = 5/13

Do the same for sine b

cos b= 9.8/11

add both the cosine value

(5/13)+(9.8/11)=1.28 or 912/715 in fraction form