For this case we have the following data:


So that the figure can be a rectangle, its diagonals must be equal, that is, 
In this way we have:

Clearing x we have:


Thus, x must be equal to 10 so that the figure is a rectangle.
Answer:

Option A
B or d are most likely it I could be wrong if I am, I am so sorry:)
Answer:
pic attached
Step-by-step explanation:
hope it helps..
Answer:
+213 is the correct answer
Answer:
12.29
Step-by-step explanation: