Even though you used the same name variables in your main method and inside your function, they are not the same variables.
Currently in main, the only variable that you assign a value to is
side_square = 3.2; and yet you are passing 3 values to your function.
Did you assign any values to the other variables before making a call to the function?
Also your function is returning a type double, but you are calling it as if it was a void function that is not returning a value. You either need to store the returned value in another variable or else use it inside a print statement.
Function call should look like this:
CODE
newValue = area_and_perimeter_of_square( side_square, area_square, perimeter_square );
Or this:
CODE
printf("%.2f", area_and_perimeter_of_square( side_square, area_square, perimeter_square );
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