Answer:
The length of diagonal XU is 6.40 units
Step-by-step explanation:
* Lets explain how to find the distance between two points
- The rule of the distance between two points 
and
is:

* Lets solve the problem
-From the attached figure:
- The coordinates of the vertex X are (2 , 2)
- The coordinates of the vertex U are (-2 , 7)
∴ The point
= (2 , 2)
∴ The point
= (-2 , 7)
∴ 
∴ 
∵ 
∴ 
∵ 
∴ d = 6.40
* The length of diagonal XU is 6.40 units
ANSWER
15.9
EXPLANATION
Given:
A right-triangle with two sides and an angle
Desired Outcome:
The value of x
Apply the SOH CAH TOA rule

Hence, the value of x is 15.9 (rounded to the nearest tenth).