Simplfy using positive exponents

I'm having trouble figuring out these problems

3x 2 ( 2 is the power)2y -4(-4 is the power)
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2x -2 (-2 is the power) 3y4 (4 is the power)



I think i start with 2x2(power)y3 4(power)
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3x 2 (power) 2y 4 (power)

to make the - powers into a postive power.. then I am stuck [/list][/b][/code][/quote][/u][/i]

\(\displaystyle \L \frac{3x^22y^{-4}}{2x^{-2}3y^4}\)

note that the 3's and the 2's in the numerator and denominator cancel ...

\(\displaystyle \L \frac{x^2y^{-4}}{x^{-2}y^4}\)

\(\displaystyle \L \frac{x^2x^2}{y^4y^4} = \frac{x^4}{y^8}\)