Answer:
x=6.6 y=12
Explanation:
To know this problem, you need to know the Pythagorean theorem, though I think you know this since it seems like you are doing a quiz or something like that. 
 +
 + 
 =
 = 

Solving x:
- Plug the numbers in
  + +
  = =
  
- 77.44+
  =121 =121
- 121-77.44=43.56
  =43.56 =43.56
  = =
  
- x=6.6
Solving for y:
- Plug the numbers in
  
This might be too late, but I hope you were able to do well on your thing!
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