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2 years ago

Combine the radicals. 3√5-8√5+2√5

Mathematics

1 answer:

weeeeeb [17]2 years ago

7 0

Answer: $-3\sqrt{5}$

-3 times the square root of 5

=============================================

Explanation:

Let $x = \sqrt{5}$

Replace all the root 5 terms with x and we go from

$3\sqrt{5}-8\sqrt{5}+2\sqrt{5}$

$3x-8x+2x$

From here, combine like terms to get

$3x-8x+2x = -5x+2x = -3x$

and the last thing to do is replace the x with sqrt(5)

$-3x = -3\sqrt{5}$

Meaning that,

$3x-8x+2x = -3x$

$3\sqrt{5}-8\sqrt{5}+2\sqrt{5} = -3\sqrt{5}$

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Answer:

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You're testing the claim that the mean difference is greater than 0.7.

At the null hypothesis, we test if it is 0.7 or less, that is:

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The test statistic is:

$t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}$

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