Answer:

Step-by-step explanation:
Let points D, E and F have coordinates
and 
1. Midpoint M of segment DF has coordinates

2. Midpoint N of segment EF has coordinates

3. By the triangle midline theorem, midline MN is parallel to the side DE of the triangle DEF, then points M and N are endpoints of the midsegment for DEF that is parallel to DE.
What is the rest of the question
As there are multiple answers going with trial and error seems good in this case.
A
5.00 + 5.00 + 5.00 + 5.00 = 20.00
3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 = 31.5
20.00 + 31.5 = 51.5
B
5.00 + 5.00 + 5.00 + 5.00 = 20.00
3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 = 35.00
20.00 + 35.00 = 55.00
C
5.00 + 5.00 + 5.00 = 15.00
3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 = 31.5
15.00 + 31.5 =46.5
Knowing that for the first one all A,B, and C were wrong we can determine that D is the answer. But wait if I made one mistake and didn't understand if $156.5 is equivalent to $156.50 that would mean A is correct.
Always recheck your answers and good luck,
Jon
The area is 84.
What I do it cut the polygon into something easier like a square and rectangle.
Rectangle: 6•12=72
Square: 4•3=12
Add them together and you have 84
Answer:
9
Step-by-step explanation:
The constant is the plain number that doesn't have a letter attached.