Answer:
<h2><u>
x = 8.2</u></h2>
Step-by-step explanation:
A^2+B^2=C^2 is the pythagorean theorem to find a missing siede of a triangle.
First triangle on the right:
5^2+B^2=10^2
25+B^2=100
B^2=75
B=8.66025404
B=8.7
Second triangle of left:
3^2+B^2=8.7^2
9+B^2=75.69
B^2=66.69
B= 8.16639455
B=8.2
x=8.2
C. A function can only have one y value for an x value
The answer is the 3rd one
check the picture below.

it cannot be -1, because is a seconds amount after moving.
The answer seems to be D!!