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Trigonometry assignment


uzair2010

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Hi everyone,

the math prob is:

Thw world's fastest roller coster is at six flags magic mountain. At the start, riders are shot forward and then up a tower. Then they begin the backward decent. The cars reach a speed of 160 KM/Hr in 7 seconds during the desent. From a point 100 meters from a foot of tower, the angle of elivation of the top of the tower is 52'(degrees) find the height of the tower to the nearest meter.

I dont know what formula should i use to solve the prob, can anyone please help me with that.

Thanx, Uzair

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From a point 100 meters from a foot of tower, the angle of elevation of the top of the tower is 52'(degrees) find the height of the tower to the nearest meter.
This is the only important part of the problem, or at least it contains all the information you need. Consider your definition of the tangent function (tan), and you will have the formula you need.

 

 

MrSandman, how on earth did you get that?

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Formula=

 

100_____x

----- = ------ or 100:28=x:52 or 100/28=x/52

28_____52

 

 

cross multiply and divide

 

Have questions on how I got it ask. It's nothing to do with decent.

 

Let's look at SandMan's formula here:

 

100 meters / 28 unknown units = x meters / 52 degrees

 

so, the unknown units on 28 must be degrees, but what is 28 degrees? 90 degrees minus 52 would be 38. So, the 28 is either wrong or just made up.

 

Not only that, but the lengths and angles aren't in perfect proportion, that's why the trig functions exist.

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Crap I meant 38 and it makes perfect sense. Now look at it.

 

The ratios stay the same with a right triangle I thought the same thing when I was veiwing this at midnight this problem doesn't need tang. Wait unless the are saying this tower isn't 90 degrees did I miss something??

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Yes they do!!!! 52degress is a set angle along with 90 with what I can see the angles must equal a total of 180. Show that if you compare the length to the angles. The have the same ratio. take a triangle with 45 45 and 90 and have the base 100m. the adjacent side will be a 100. See?

 

I know I'm not suppose to give the answer, but since this is days old I think it is okay.

 

Approx:

136.84m

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Making a mountain out of molehill here. It is a simple problem. Deserving a simple solution. I'm using ratios between sides and angles. They are both related. Sure it trig, but you don't have to use a calc to solve this problem.

 

Fswd: He brought the "God" topic up.

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Fswd is right, your answer is 8m too long. If you want to be able to relate the ratio an angle and its opposite side to the ratio of a separate angle and its opposite side, you use the law of sines, not what you're doing.

 

In any case, we don't even need the law of sines, because 100tan(52) gives the correct answer.

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Making a mountain out of molehill here. It is a simple problem. Deserving a simple solution. I'm using ratios between sides and angles. They are both related. Sure it trig, but you don't have to use a calc to solve this problem.

 

Fswd: He brought the "God" topic up.

 

That is exactly what the tan function does, but different, as you cant divide metres by angles cuz the goniometric functions need to be fed dimentionless figures to get angles, which you get by for example divide metres on eachother.

 

Oh well i'm using tan just in a wrong form.

 

You arent using it at all.

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Oh well i'm using tan just in a simpler form.

 

There is no simpler "form" for tangent. It is a defined function. Sandman, get out your ruler and protractor, and draw a triangle with a side of 100 centimeters, and the angle of 52 degree, and you will see that your answer is wrong. It is as simple as that.

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Yes, I see that now. I don't like using formulas that some guy figured out. I'd rather figure the formula by myself. One reason I thought it work is that if you have a 45 90 45 degree triangle the ratio would work but that is probably just when it is 45.

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