Question

What does multiplying a number by -1 mean?

Answer 1

It’s just the same like 1x7=7 :)

Answer 2

If the number being multiplied by -1 is positive it just turns it negative, but if the number being multiplied by -1 is also negative it becomes positive. Basically if flips the sign.

Explanation:

EX) 25 x -1 = -25

EX) -25 x -1 = 25