Finding the perimeter

Question

A triangle has a perimeter of 43 inches. Find the three sides if one side is 18 inches larger than the smallest and the third side is three times the smallest

Answer 1

Ok. The perimeter of any polygon is the sum of the measurements of each of its sides. A triangle has three sides. Let's allow x to equal the smallest side. Then the third side = 3x. The remaining side can be expressed as x + 18. We know the perimeter of this triangle is 43. So we have:

43 = x + (x + 18) + 3x We need to combine like terms
43 = 2x + 18 + 3x
43 = 5x + 18
25 = 5x
x = 5 in.

The 3rd side is 3x = 3 * 5 = 15 in.
The remaining side is x + 18 = 5 + 18 = 23 in.