Don't go by my answers pls
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Answer:
19) ( [tex]\frac{-2}{5}[/tex])^2 = [tex]\frac{4}{25}[/tex]
20) -[tex]9^{2}[/tex] = -81
21) [tex]2^{4}[/tex] = 16
Step-by-step explanation:
The only wrong ones are
19) ( [tex]\frac{-2}{5}[/tex])^2 = [tex]\frac{4}{25}[/tex]
20) -[tex]9^{2}[/tex] = -81 ... negative is not inside a parenthesis that's why it is still negative
21) you can add another way is [tex]2^{4}[/tex] = 16
Everything else looks good. Great job!