Sending one digit variable serially

Good day, I'm trying to send the variable x through serial to my arduino. The only problem is, when i monitor my serialport, the value of x doesn't appear as it should and I need it to. This is my very simplified code:

clear;

x=6;

x=x+3;

x;

s=serialport("COM1",9600);

pause(1);

write(s,x,"char");

In my serial monitor, it only creates a bunch of spaces and I've tried all the different types of variable types, i.e "uint", "int", "single" etc availeble. However, as you can see the varaible x should be 9 and I want to send 9. When I use single, I get values on the ASCII table, however subtracting the right amount to achieve the '9' doesn't seem to work. Any help would be much appreciated!