Fill in the Blanks - A Math Mystery : 6 _ 5 _ 4 _ 2 = -4

This puzzle necessitates rapid thinking and problem solving aptitude. You'll be given a formulae with three operators missing. Your task is to locate the absent operators and fill in the formulae. It's a superb way to evaluate your understanding of basic mathematics and enhance your reasoning skills. Prepare to exercise your intellect and have fun!