Find the exact value of cos(u+v), sin u=8/17 and cos v =-60/61

Hi
Question : 
Find the exact value of cos(u+v), sin u=8/17 and cos v =-60/61 
 
(8/17+60/61)
(1,36+36.6) =37.96

Answer : 
37.96 

I hope it helps and if it is correct please press brainlest
~Rie

The greatest common factor of 72 & 81 is 9 because both numbers are equally divisible by 9 (ex:8x9=72 & 9x9=81). No other number greater than 9 equally divides between the two terms. That's the answer to part 1. I'll keep looking for the answer to part 2.