Answer:
13.6 inches
Step-by-step explanation:
We can use Pythagorean theorem: 
Let c be the diagonal length, a for length, and b for width.
Substitute the values.

c=13.6 inches
Answer:
C
Step-by-step explanation:
there are infinitely many solutions since different values of x and y will work for this simultaneous equation
Choice B:
The line intersects at both points (0,-3) and (1,0)
(I can not specifically see the number on the grid if there is any but that is what I would put for the answer based on what I see)
If you want me to explain it more I can try to! :)
I hope this helps