Answer: 
Step-by-step explanation:
Given
The perimeter of one equilateral triangle is P
The lengths of the equilateral triangle are equal
Suppose x is the length of each side

i.e.

3x^2+11x-4=10x-1
3x^2+11x-10x-4+1=0
3x^2+x-3=0
Δ=1^1-4*3*(-3)=1+36=37
x1=(-1+V37)/6
x2=( -1-V37)/6
<span>The distance from the vertex to the centroid is twice the distance from the centroid to the side.
This means that 3x + 5 = 2 * (2x)
</span><span>3x + 5 = 4x
x = 5
Source:
http://www.1728.org/trictr.htm
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