
- 5 = -7 .
____________________________________________This would be one way to write the expresion/equation; in which "x" represents the unknown number.
Now, to solve for "x" ;
____________________________________________Given:
____________________________________________
- 5 = -7 ;
Add "5" to EACH SIDE of the equation:
_____________________________________________
- 5 + 5 = -7 + 5 ;
to get:

= -2 ;
x = (-2 * 3) ;
_________________________________x = - 6 .
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