Question

The length of each side of an equilateral triangle is increased by 5 inches, so the perimeter is now 60 inches. How do you find the original length of each side of the equilateral triangle?

Answer 1

The original sides were 15 inches.

Explanation:

Each side of an equilateral triangle starts with length `x`. They are all extended by 5 inches (so now each side is `x+5` and the sum of all three sides together is 60. So we have:

`3(x+5)=60`

`3x+15=60`

`3x=45`

`x=15`

The original sides were 15 inches.