Mengapa mengalikan dua angka negatif menjadi positif?

Penjelasan umum :

Jika saya berkata "Makan", saya mempersilahkan anda untuk makan (positif), tetapi jika saya berkata "Jangan Makan", saya mengatakan kebalikannya (negatif).

Maka, jika saya berkata "Jangan Jangan Makan" , artinya saya berkata "Makan".

Penjelasan khusus :

Ingat kembali Garis Bilangan !!!

 

Sumber : http://www.mathsisfun.com/multiplying-negatives.html

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