Answer:
I'd need to see more, but because they are the same number just positive and negative they'd be on opposite ends of zero
Start by representing the lengths of the three sides of your triangle:
first side: x-4 (inches)
second side: x (inches)
third side: (x-4) + 3 (inches)
Add these three quantities up to obtain a formula for the perimeter, and set your sum equal to the given perimeter (15 inches):
x-4 + x + x-4 -3 = 15
3x-11=15
3x=26
x=26/3
Thus, the length of the 2nd side is 26/3; that of the first side is 26/3-4, or 14/3; and that of the third side is 14/3+3, or 23/3 (all measurements in inches).

The given two polygons are similar to one another ~
Sides of the given polygons are in ratio of :

to put in simple Ratio ~
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So, the sides of the larger polygon are :
Now, to find the Perimeter of larger polygon ~ add the side length of all sides :


I got 70
Combination=n!/((n-r)!r!)
=8!/((8-4)!*4!)
=8*7*6*5*4!/(4!*4!)
=8*7*6*5/(4*3*2)
=70 ways