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3 years ago

13

Work out the value of 1. 7/2 -a ² 2. 3x-8 = 19

2 answers:

Zanzabum3 years ago

8 0

Answer:

1. -45 1/2.

2. x = 9.

Step-by-step explanation:

a/b - a^b when a = 7 and b = 2

= 7/2 - 7^2

= 7/2 - 49

= -91/2

= -45 1/2.

3x - 8 = 19

3x = 19 + 8 = 27

x = 9.

ratelena [41]3 years ago

3 0

Yes it is very easy, but

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2 years ago

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Answer:

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Step-by-step explanation:

Given

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$v =$

Required:

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$cos\theta = \frac{-16}{10\sqrt{26}}$

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Take arccos of both sides

$\theta = cos^{-1}(\frac{-8}{5\sqrt{26}})$

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$\theta = cos^{-1}(-0.31378701706)$

$\theta = 108.288386087$

<em></em> $\theta = 108.29$ <em> (approximated)</em>

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