anonymous 3 years ago I need help with question. Im gonna download question.

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who opens .docx anymore?

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you can open do docx

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you need to use trigonometric functions

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i got cos 50=x/90 right

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so i got 57.9

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The cosine of a 50° angle is 57.9 right

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which part the first blank is asking which function to use to find the height

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part 1 i think its cosine

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if yo are using cos(50)=x/90

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yes that's what i did

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and i got 57.9

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then the next part is asking for the reverse how do you find the cosine function with the two sides

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57.8

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then input the cosine of 50 in your calculator for the next blank

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its asking this this represents the value created when length _____ is divided by ______ feet.

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the angle is the value when you divide the sides accordingly

Cos 50 degrees is 0.6428

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The cosine of a 50° angle is 57.9 is this right for the second part

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all the trig functions are is a relationship between the lengths of sides if you divide two known sides and take that data it represents and angle.

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so like radar has said the cosine of 50 is .6428 so the sides divided are also .6428

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57.8 is the height of the tower because you multiplied the hypotenuse by the cosine to find x

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so it will be .6428x.6428

Cos is the adjacent side divided by the hypotenusel.

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what happens if you divide the side x by the side of 90

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adjacemt side is x right and hypotenusel is 90

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so 57.8 divided by 90

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that's what i got

$\cos 50^{0}=x/90 ft$

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you get .6422

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i got 57.9

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roughly the same as the cosine for 50 degrees

$x=.6428 \times90$

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that is what we have so far

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so it would be 57.9

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so x side is 57.9

Yes

when angle was 50 degrees

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$\cos(50^{0})=\frac{ adjacent }{ hypotenuse}$

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The cosine of a 50° angle is .6422 right

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the first question only wanted to know that you would use the cosine function to find x

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the next blank wants you to input the cosine of 50 which you have .6422

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its .6428

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yes if you type in cos50 in your calculator that is what you get

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this represents the value created when length ____ is divided by ____ feet.

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if you look at the funtion you know that it is x divided by the 90 feet if you divide the value you got for x by 90 it is about the same as cos 50

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when length is 50 is divided by x feet right

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no 50 is the angle you want the height of the tower divided by the lenght of the decline which is 90

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when length is 90 divided by x feet

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|dw:1349578522617:dw|

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right

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see how it is lenght x divided by 90 feet

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ok i see now x/90

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that is a balanced equation if you divide that you get the same value as you did when you input cos of 50 into your calculator

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ok

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If the angle of declination changed to 60°, the cosine would be 0.5; now the length of x would be ________ feet.

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use the same equation with the cos of 60 instead

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so its gonna be cos(60)=x/90

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$\cos(60^{0})=\frac{ x }{ 90ft }$

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so now you need to solve for x

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so it would be 45

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yes one more blank left

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there is two ways to solve for this but you are suppose to use a trig function

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there are srry

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0.5

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If the angle of declination changed to 60°, the angle of inclination would be _____ degrees.

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no it wants to know the angle of inclination which is the angle from the bottom

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|dw:1349579070499:dw|

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the angel theta is unknown do you know which trig function to use to solve it

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not sure

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so theta is 60 degrees right

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if you look at the trig functions there are sin=opposite / hypotenuse cos which we covered and tangent = opposite / adjacent

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ok

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so you want to use the sine function

From reading the problem, I believe you could solve simply from the fact you are working with a right triangle, and the sum of the two acute angles equals 90 degrees.

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|dw:1349579230668:dw|

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so apposite side is 45 right

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yes

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so we trying to find the bottom right

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yes the bottom angle

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on your calculator you push the 2nd button then 45/90

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i got 0.5

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you need the inverse sine of .5 which is 2nd sin .5

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are you using a ti calculator

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no my iphone

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you need to look for $\sin ^{-1}$

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ok

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you press sin ^-1

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and than 45/90

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is that a button

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yes its sin^(-1)

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yes what do you get when you put that in

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0.5

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.5 is what you get when you do the division without the sine function I am not sure what your calculator is doing

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when you get the true inverse sine you will get 30 degrees

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i got 30

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that is correct know do you notice that the 30 you got and the 60 degree other angle add up to 90 and the right angle is also 90 every triangle has 180 degrees in it so you could have just found the missing amount from 180

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that is a link to a tutorial that might be able to help

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