check my answer?
simplify the expression;
(-5i)(-3i)
this would be 15i since a - times a - is a positive right?

Question

check my answer?
simplify the expression;
(-5i)(-3i)
this would be 15i since a - times a - is a positive right?

math&ing001 · Answer

A - times a - is indeed a positive, but i*i is not equal to i

anonymous · Answer

oh wait, I is equal to -1. so that would make it -15i  wouldn't it?

math&ing001 · Answer

i*i=i^2=-1

anonymous · Answer

That'll be 15i to the second power, since you would add the exponents.

anonymous · Answer

15i^2 isn't an answer choice...
it would be -15i wouldn't it?

math&ing001 · Answer

It would be -15

anonymous · Answer

Wait, what type of math do you have?  Because that's the right answer; you have to add the exponents and multiply like bases.

anonymous · Answer

I'm in Algreba 101 and that seems to be the correct one...

anonymous · Answer

its a compound inequality so its different, and im not sure, because 15i^2  wasn't one of the answers. but yeah, I would think that your right. that's not one of the answers though so idk

anonymous · Answer

Oh, okay.

anonymous · Answer

thanks for your input though!

anonymous · Answer

You're welcome!

math&ing001 · Answer

@Walmart789456 those are called imaginary numbers which are defined by the property i^2=-1