You can design your functions to accept parameters by modifying the definition to include as many as you want. You need to give each parameter the name you will be using to refer to it inside the function - when you later call that function, PHP will rename the values to fit your function definition, like this:
After running that script, $mynum will be set to 50. The multiply() function could have been rewritten so that it was just one line: return $num1 * $num2, but it is good to show that you can make your functions as long as you want.
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