4x^-1y
10xy^-2
Now I know its 2/5 but I just dont know what to do with the negative exponents.
Another quick one.... (3/4)^-2
Is that just 9/8?
And I don't believe this is factorable... 36x^2 +49
Am I right?
Do you know negative exponents? $\displaystyle x^{-y}=\frac{1}{x^y}$ and $\displaystyle \frac{1}{x^{-y}}=x^y $
So you have: $\displaystyle \frac{4yx{-1}}{10xy^{-2}}$
I would split it up to be: $\displaystyle \frac{4y}{10x}\times x^{-1}\times \frac{1}{y^{-2}}$
Now get rid of the negative exponents: $\displaystyle \frac{4y}{10x}\times \frac{1}{x}\times y^2$
Multiply to get: $\displaystyle \frac{4y \times y^2}{10x\times x}$
Therefore: $\displaystyle \frac{4y^3}{10x^2}$
Which can be changed to: $\displaystyle \frac{2y^3}{5x^2}$
but that's as far as you can go.
$\displaystyle \left(\frac{3}{4}\right)^{-2}=\frac{3^{-2}}{4^{-2}}=\frac{4^2}{3^2}=\frac{16}{9}$Another quick one.... (3/4)^-2
Is that just 9/8?
I don't think it is, but 36x^2-49 is.And I don't believe this is factorable... 36x^2 +49
Am I right?
Here is a link that clears the negative exponents, it basically means something like this:
N^-x = 1/N^x
Math Forum - Ask Dr. Math Archives: Negative Exponents
On top of your problem there, is it 4x^-1 and then multiply by "y" or is it just 4x to the negative 1y power?
And the factoring, you can't factor that, but if in between it was a minus sign then you can: 36x^2-49 = (6x+7)(6x-7)
Hope this helps
Derg