Answer:
15.9 centimeters
Step-by-step explanation:
the information we have is:
Perimeter: 
Number of sides of the polygon: 
since each side has equal length, we can use the following equation to find the measure of one side of the polygon, the equation for perimeter:

where n is the number of sides and
is the length of each side.
So we clear for
and we get:

and subtituting the known values:

each side is 15.6 centimeters long
If T is the midpoint, then that means its exactly 1/2 of the way between 2 points
this means we can set the 2 given values equal
4x - 3 = 2x + 7
first move like terms to the same side
2x = 10
x = 5
now that we know the length of x, we plug it back in to get the length
4x - 3 + 2x + 7 = 6x + 4
6(5) + 4 = 34
We will determine the length of the segment DF as follows:
*We have that the triangles are similar, and therefore the following is true:

Now, we solve for DF:

From this, we have that the length of the segment DF equals 2.68 units.
(3x+4) (x+2)
This gives you 3x^2 + 6x + 4x + 8
Which simplifies to 3x^2 + 10x + 8
Correct: m,b,c
incorrect: a,n,c
it’s hard to explain