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3 years ago

9

Number ten please thanks

1 answer:

BlackZzzverrR [31]3 years ago

5 0

-3^2= -(3)^2

The exponent of 2 only applies to the number 3. -(3)^2 should equal -9. This is true because according to the order of operations, exponents should be evaluated before multiplication. The negative sign here represents -1* 3^2.
If you want to find -3 to the power of 2 it must be written (-3)^2.

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3 years ago

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Step-by-step explanation:

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If they are using a 85% level of confidence, how large of a sample is required to estimate the mean usage of water?

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$0.14\sqrt{n} = 1.44*1.3$

$\sqrt{n} = \frac{1.44*1.3}{0.14}$

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Rounding up

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