The third side can be represented by D) 
Step-by-step explanation:
Step 1:
According to the Pythagorean theorem, the square of the hypotenuse will be equal to the sum of the squares of the other two sides.
In the given triangle, the hypotenuse is the side that is represented by z. Another side on the triangle is represented by the value y.
Step 2:
Assume the other side of the triangle measures x units.
So according to the Pythagorean theorem,

which is option D.
Answer:
1) take the first part of the equation and work it by multiplying (x+2) by 3
3(x+2)+x
3x +6+x
2)put the answer you got into the question you were given
3x + 6+x =2x +16
3)group the x variables and the non x variables
3x +x -2x =16 -6
4) Now work the equation you have
3x+x-2x=16-6
4x-2x=16-6
2x=16-6
2x=10
5) you divide both sides by the x variable
2x=10
2x/2 =10/2
x=5
therefore x is 5
1 inch = 12 miles
so 6 1/2 inches (or 6.5 inches) = 6.5 * 12 = 78 miles <===