When are numbers negative?

I did two problems just now and both had positive answers, while I mistakenly got negative answers.

The first,

I thought it would equal 3x, since x - x = 0 and 0 - 3x = -3x

The other, While I got the opposite answer.

Can anyone explain *why* these answers aren't positive?

Re: When are numbers negative?

Just multiply -3x by minus one.

For the second problem:

You could have just multiplied out instead.

Re: When are numbers negative?

Quote:

Originally Posted by

**Nervous** I did two problems just now and both had positive answers, while I mistakenly got negative answers.

The first,

I thought it would equal 3x, since x - x = 0 and 0 - 3x = -3x

The other,

While I got the opposite answer.

Can anyone explain

*why* these answers aren't positive?

what does "the first" mean ? I don't see an equation ...

fyi, the second equation has no solution for x.