Answer:
4m +3
Explanation:
The perimeter of a polygon is the sum of the lengths of its sides.
Application
For a triangle with sides of length a, b, and c, the perimeter is ...
P = a +b +c
P = (3m) +(4 -m) +(2m -1) = (3-1+2)m +(4-1)
P = 4m +3
The perimeter of the triangle is 4m+3.
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Additional comment
In order for this to be a legitimate triangle, the value of m must satisfy ...
5/6 < m < 3/2