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JavaScript JavaScript Foundations Functions Scope

Jacob Tennyson
Jacob Tennyson
6,240 Points

challenge task 1 0f 1 Scope

I have no idea whats going on here. Can somebody explain this differently.

When the 'hypotenuse' function is called the value of 'x' changes from 1. Fix it so that 'x' is still 1 in the global scope.

<!DOCTYPE html>
<html lang="en">
    <title>JavaScript Foundations: Functions</title>
      html {
        background: #FAFAFA;
        font-family: sans-serif;
    <h1>JavaScript Foundations</h1>
    <h2>Functions: Scope</h2>

      var x = 1;
      var y = 1;

      function hypotenuse(a , b) {
        var cSquared = a * a + b * b;
        x = Math.sqrt(cSquared);
        return x;

      hypotenuse(x, y);


1 Answer

Chris Shaw
Chris Shaw
26,662 Points

Hi Jacob,

Essentially all this task is asking for is to prevent the local variable x within the hypotenuse function from altering the global variable x, we can do this by scoping the variable x in our function by prepending it with the var keyword.

var x = Math.sqrt(cSquared);

Happy coding!

Jacob Tennyson
Jacob Tennyson
6,240 Points

Thanks. I had a feeling it was really simple...This stuff is overwhelming sometimes.