Respuesta :

8/10 = 4/5 =  0.8

Step-by-step explanation:

Step 1 :

The given triangle is a right angle triangle with sides as follows :

AB = 10

BC =  6

AC = 8

And angle C is right angle.

Step 2 :

To find the cosine of the required triangle , we have to divide the length of  triangle's adjacent side by the triangle's hypotenuse

Here the adjacent side of the given triangle is 8 and the hypotenuse is 10

So the cosine of the required triangle is 8/10  =  0.8