Simplify the expression:

-20a ^{-2}b ^{-7} / 5a ^{-5}b ^{3}

Write your answer without negative exponents.

Question

Simplify the expression:

-20a ^{-2}b ^{-7} / 5a ^{-5}b ^{3}

Write your answer without negative exponents.

anonymous · Answer

$$-20a ^{-2}b ^{-7} / 5a ^{-5}b ^{3}$$

There is the equation how it is supposed to look.

skullpatrol · Answer

$$\frac{-20a ^{-2}b ^{-7}}{ 5a ^{-5}b ^{3}}$$

anonymous · Answer

Yeah, thats the equation. I'm just a little lost.

skullpatrol · Answer

The first thing you should understand is this is not an "equation," it is an "expression" do you know why?

anonymous · Answer

Because it doesn't have an equals sign to equal a value.

skullpatrol · Answer

Correct :)
An "equation" must have an "equals sign"

anonymous · Answer

So when I'm dividing two numbers like this, don't I divide all whole number and subtract like variables?

skullpatrol · Answer

There are certain "rules of exponents" that you should understand first. You are perfectly correct in working with "like variables" by this I mean the bases must be the same.

anonymous · Answer

So I can subtract the exponents on say $$a^{-2}$$ and $$a ^{-5}$$?

skullpatrol · Answer

Yes, -3-(-5) is the exponent on a.

anonymous · Answer

But the first A has a negative two on it?

anonymous · Answer

And then that gives us -7, but the question says to write the answer without negative exponents. This is where I start to get lost...

skullpatrol · Answer

Ooops I meant -2-(-5)  is the exponent on a.

anonymous · Answer

Okay so that gives us A^-7, and like I said... the original question asks to write it without negative exponents. I kinda get lost whenever I come to this point.

skullpatrol · Answer

What is -2-(-5)=?

anonymous · Answer

OH! its a negative negative... so the answer to that would be 3?

skullpatrol · Answer

Yes :)

anonymous · Answer

Okay, and just one final question. On the -20 / 5... its just that, right? -20 / 5?

anonymous · Answer

Actually one more question now that I look at that. The b^-7 and b^3 would be -7 + 3, correct?

skullpatrol · Answer

How many times does 5 go into 20?

anonymous · Answer

4

skullpatrol · Answer

So -20 / 5 =?

anonymous · Answer

-4

skullpatrol · Answer

Correct :)

anonymous · Answer

Okay, now one more question (sorry). The -7 + 3 on the B's would be -4. What am I not seeing there?

skullpatrol · Answer

The exponent is 10 on b and it belongs in the denominator.

anonymous · Answer

How?

skullpatrol · Answer

3-(-7)

anonymous · Answer

Ah okay, so it would be $$-4a ^{3}b ^{10}$$

skullpatrol · Answer

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