findPerimeterOctagon()

Step 1: Understand the Problem

The first step in solving this problem is understanding what an octagon is and how to calculate its perimeter. In geometry, an octagon is a polygon with eight sides. The perimeter of an octagon (or any polygon) is just the sum of the lengths of its sides.

Since we are looking to calculate the perimeter of a regular octagon - an octagon where all sides are of equal length - the calculation becomes much simpler. We simply multiply the length of one side by 8.

Step 2: Define the Function

Let us now start creating our function. In Javascript, we define a function using the keyword function, followed by the name of the function. In our case, we are calling the function findPerimeterOctagon. This function will take one argument - the length of one side of the octagon.

function findPerimeterOctagon(sideLength) {
  
}

Step 3: Calculating the Perimeter

Inside our function, we need to calculate the perimeter of the octagon. As explained earlier, for a regular octagon, this is done by multiplying the length of one side by 8.

function findPerimeterOctagon(sideLength) {
  var perimeter = 8 * sideLength;
}

Step 4: Returning the Result

Evaluation of the perimeter isn't enough. We need our function to return this value to the caller. This is done using the return keyword in Javascript.

function findPerimeterOctagon(sideLength) {
  var perimeter = 8 * sideLength;
  return perimeter;
}

Step 5: Testing the Function

Our function is now complete. However, it's always a good idea to test our code to make sure it works correctly. Let's call our function with a test input of 5, and log the result:

console.log(findPerimeterOctagon(5));  // Output: 40

Conclusion

And there we have it - a simple Javascript function to calculate the perimeter of a regular octagon. The full code for our function is as follows:

function findPerimeterOctagon(sideLength) {
  var perimeter = 8 * sideLength;
  return perimeter;
}

console.log(findPerimeterOctagon(5));  // Output: 40

By following these steps, breaks down the problem into bite-sized tasks, you can tackle even more complex programming problems. Happy coding!