ok, I have this question that I thought I had the answer to, but the "answer" is something different. Check out the stem:

If a = 3 and b = -2, what is the value of \(a^2 + 3ab - b^2\)?

This should be easy, and the hangup I have is on the \(-b^2\).

I have set it up this way via substitution:

\((3)^2 + 3(3)(-2)-(-2)^2\)

It appears to me the answer would be a -13.

The above becomes this:

\(9 -18 - 4 = -13\)

Am I correct in doing the square of the -2 first, so then you have - 4 (that's minus 4, or minus a positive 4, not negative 4)?

The answer is supposedly 5, which would mean the \(-(-2)^2\) would have flipped the sign of -2 to a +2 and then squared that, for a + 4.

What is the correct order to do this in? I thought exponents came before addition/substraction?

Jarod

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J Allen Morris

**I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.

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