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3 years ago

8

Evaluate the expression when x = –18. x-10/4 Very confused on how to solve this one.

1 answer:

Amiraneli [1.4K]3 years ago

5 0

Well evaluate means solve . so you just substitute the -18 in place of x you'll get -18-10/ 4

which is -28/4 = -7

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Please help me for the love of God if i fail I have to repeat the class

Elena-2011 [213]

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$x$ is in quadrant II, so $\sin x>0$ .

Recall that for any angle $\alpha$ ,

$\sin^2\alpha+\cos^2\alpha=1$

Then with the conditions determined above, we get

$\cos\theta=\sqrt{1-\left(\dfrac45\right)^2}=\dfrac35$

and

$\sin x=\sqrt{1-\left(-\dfrac5{13}\right)^2}=\dfrac{12}{13}$

Now recall the compound angle formulas:

$\sin(\alpha\pm\beta)=\sin\alpha\cos\beta\pm\cos\alpha\sin\beta$

$\cos(\alpha\pm\beta)=\cos\alpha\cos\beta\mp\sin\alpha\sin\beta$

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as well as the definition of tangent:

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Then

1. $\sin(\theta+x)=\sin\theta\cos x+\cos\theta\sin x=\dfrac{16}{65}$

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$\cos^2\dfrac\alpha2=\dfrac{1+\cos\alpha}2$

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$\implies\tan^2\dfrac\alpha2=\dfrac{1-\cos\alpha}{1+\cos\alpha}$

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3 years ago

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Answer:

audrey_111506

Step-by-step explanation:

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3 years ago

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Please help me!<br><br> Solve for x<br><br> 4−(2x+4)=5

Helga [31]

<span>4−(2x+4)=5
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3 years ago

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blsea [12.9K]

Answer:It

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Step-by-step explanation:

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3 years ago

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kkurt [141]

Answer:

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Step-by-step explanation:

Given;

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initial time, t₀ = 3 seconds

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y(3) = 34(3) - 26(3)² = -132

The average velocity of the ball in ft/s is given as;

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Therefore, the average velocity of the ball at the given time interval is -122.3 ft/s

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3 years ago