how to read negative voltage?

Hi, does anybody know how to configure in arduino to read negative voltage? like i want to see on my serial port that the arduino is taking in is negative voltage and when i try to check that on my volt meter it will say the same (i.e. -2). im very new with arduino, i read that it can only read 0 - 5, but im sure there has to be a way. i was reading the analogReference(type) tutorial and i thought that might be the way to do it but it says do not use less than 0V or more than 5V for external reference.. please help. thank you.

What is the full range you want to measure?

Quick and dirty method. Works as long as the impedance of your signal is much less than ‘Rtop’, and ‘Rtop’ is ideally < 10kOhm.

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