Answer:
13 units
Step-by-step explanation:
So the length of those 2 points is 6+6 = 12.
The height would be 8-3 =5
Using pythagoras, you can find out the length of the line joining the 2 points so:

units
2/3 / 5/6 + 5 (3)^2
= 2/3 * 6/5 + 45
= 12/15 + 45
= 45 4/5 Answer

You are taking two times a number, which is defined as x. That is equivalent to 2x. Then, you are adding three more to that product.