Question

The perimeter of a triangle is 42 inches one side measures 18 inches the shortest side measures x inches the longest side measures 1 inch less than four times the length of the shortest find the length of the longest side

Answer 1

By writing an equation you can easily solve this:

18+ X + 4X - 1 = 42
•we need the answer to 4X-1

1. put the parts that include the X parameter in one side and the integer numbers in one side :
X + 4X = 25
5X= 25
X= 5

2. 4X-1 —> 4x5-1 = 19