How do I start a new clan? Is it just as simple as filling in a new clan name?

I was trying to use .toFixed() or .toPrecision in my answer:

return (3.141592 * circle.radius * circle.radius).toFixed(6);

and they throw the error:
TypeError: circleArea(...).toFixed is not a function
at Object.handleError
at ContextifyScript.Script.runInThisContext
at Object.runInThisContext

I'm not sure why this is so. My first guess is that because the product is being returned as a string. I tried this as well:

let area = (3.14 * circle.radius * circle.radius);
return parseFloat(area).toFixed(6);

I get the same error.

I have already peaked at the solutions and only see three instances where these Number methods are being used. All of these have the + operator tacked onto the front with some additional "bits":

return +(''+(Math.PIc.radiusc.radius).toFixed(6))

or

return +(Math.PI * r * r).toFixed(6);

or

circleArea=〸=>+(Math.PI〸.radius〸.radius).toFixed(6)

So I have two questions: Why can't I use .toFixed() as I was attempting to? and, What is the + operator doing here to make .toFixed() work?