2 negatives can be converted to a plus sign. -(-x) can be +x or just x.
-54--23
-54+23
23-54=-31
78--4
78+4=82
-48/-6
Now let's pause fer a sec. When a negative is being divided by another negative, the quotient(answer to division problem) becomes a positive.
-48/-6=8
50*-4=-200
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hope it helps
