SOLUTION: The perimeter of a triangle is 120 inches. If one side is twice the second side and the third side is 20 inches more than the second side, find the length of each side. The leng

Algebra ->  Triangles -> SOLUTION: The perimeter of a triangle is 120 inches. If one side is twice the second side and the third side is 20 inches more than the second side, find the length of each side. The leng      Log On


   

Question 246021: The perimeter of a triangle is 120 inches. If one side is twice the second side and the third side is 20 inches more than the second side, find the length of each side.
The length of the first side is ____ inches.
The length of the second side is ____ inches.
The length of the third side is _____ inches.
Answer by marcsam823(57) About Me  (Show Source):
You can put this solution on YOUR website!
one side is twice the second side so:
Let x = length of side 2
Let 2x = length of side 1
Let x + 20 = length of side 3
To find the perimeter add all three terms and set them equal to 120 (total perimiter).
x+%2B+2x+%2B+%28x%2B20%29+=+120
Combine like terms
4x+%2B+20+=+120
Subtract 20 from both sides of the equation
4x+=+100
Divide both sides by 4
x+=+25
So side 2 is equal to x = 25 inches
Side 1 = 2x = 2(25) = 50 inches
Side 3 = (x + 20) = 25 +20 = 45 inches
Check
25 + 50 + 45 = 120
120 = 120
Therefore these are the correct lengths