SOLUTION: An equilateral triangle and a regular polygon have the same perimeter. Each side of the pentagon is three inches shorter than the of the triangle. What is the perimeter of the tria

Algebra ->  Polygons -> SOLUTION: An equilateral triangle and a regular polygon have the same perimeter. Each side of the pentagon is three inches shorter than the of the triangle. What is the perimeter of the tria      Log On


   

Question 862605: An equilateral triangle and a regular polygon have the same perimeter. Each side of the pentagon is three inches shorter than the of the triangle. What is the perimeter of the triangle?
Answer by ben720(159) About Me  (Show Source):
You can put this solution on YOUR website!
Let s equal one side of the triangle
equilateral triangle P = Pentagon with s-3 sides perimeter
3s=5%28s-3%29
Distribute the 5
3s=5s-15
Subtract 5s from both sides
-2s=-15
Divide both sides by -2
s=7.5
Each side is 7.5, so the perimeter is 3(7.5), or

22.5