Learn

We can also define functions with multiple parameters.

``````function divide(\$num_one, \$num_two)
{
return \$num_one / \$num_two;
};``````

In the function above, we defined the `divide()` function. It takes in two number arguments and returns the result of dividing the first parameter by the second. Let’s look at how we invoke this function:

``````echo divide(12, 3); // Prints: 4

echo divide(3, 12); // Prints: 0.25``````

In the code above:

• First, we printed the value returned from invoking our `divide()` function with `12` and `3` as arguments.
• Next, we printed the value returned from invoking our `divide()` function with `3` and `12`.

Notice that the order we pass in the arguments decides which parameters they correspond to—the first argument we pass into `divide()` will be assigned to `\$num_one` and the second argument to `\$num_two`.

Invoking a function with fewer arguments than expected will result in an error:

``````function expectTwo(\$first, \$second)
{
return "whatever";
}

echo expectTwo("test"); // Will result in an error``````

Ok! Let’s make functions with multiple parameters!

### Instructions

1.

Write a function `calculateArea()` that takes in two number arguments—representing the height and width of a rectangle—and returns the area of that rectangle.

2.

Use `echo` to print the result of invoking your `calculateArea()` function with two number arguments.

3.

Write a function `calculateVolume()` that takes in three number arguments—representing the height, width, and depth of a box—and returns the volume of that box.

4.

Use `echo` to print the result of invoking your `calculateVolume()` function with three number arguments.