Like a bit of maths? Have a go at this...

[ms51ves3]

This is a question in my analytical methods assignment on my HNC construction course. I've already got the answer, but it's quite an easy question once you know what you're doing, just takes a little time to work out.

[rac3r]

1
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[warped one]

Well if your 200m closer the angle should still be 45, that is dependant on you following a straight line towards the same corner.

I would assume that you have changed your perspective and thus to me the question is null, unless you are following a compound mitre which would add another set of trig into the equation.

Basically my brain is fried from trying to follow this.
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amnesia - Never in the history of usernames has one been more accurate. Warped indeed. You sir are a fecking oddball.

[ms51ves3]

Are you stupid, Warped?

Stand at the side of your house from ten metres away, look up to the top of it, now stand with you chest touching the wall of your house and look up to the top of it again.

As if by magic, the angle of your head has changed

You're going 200 metres along the ground, not up a cherry picker towards the top of the building at the same angle.

Rac3r - No

[rac3r]

[warped one]

[blurredman]

I didn't read it through properly. I am a dick.

I know it's pythagoras triangle, you work out the final angle degree by using the 45 and 80 figures.
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[warped one]

From my understanding of trig you need 2 measurements.

That 200m closer could be from a mile away or the solar system. IT just doesn't work out in my head.
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amnesia - Never in the history of usernames has one been more accurate. Warped indeed. You sir are a fecking oddball.

[bacon]

242.81m

basic maths people

[HP]

The height of the bulding is the the distance of which you was away originally, however im struggling to find an exact figure for the distance.
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[Frost]

242.8

√!∞

[Pete.]

Autocad says 242.81m
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[DJH]

I don't know.

[L4Isoside]

So in "everyday" life, when will I ever need to do this?

[Frost]

If you're an engineer wanting to know how high something is and you don't have a tape measure long enough?
Something similar to this was first used to calculate the size of the earth.

[L4Isoside]

[stinkwheel]

https://i48.photobucket.com/albums/f216/stinkwheel/trig.png

Fukin' maths!

Stinkwheel used his head, (but a scientific calculator, not Trig tables)

EDIT: Also. I've drunk 5 pints of magners.

EDIT 2: I should also add, it's been 16 years since I did maths and I also claim full marks for showing my working.
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[stinkwheel]

[ollieholt]

hehe pervascope.... thats hilarous!
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[swanny]

well if you stand next to the building and look up, its at 90 degree's unless its built by cowboys in which case the whole equation is wrong.
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[ms51ves3]

[Suntan Sid]

The answer is:-

242.814m

You will never have to do that calculation in real life, you ask your CAD buddy to spare 10 secs of their time to work it out for you!

[Charlie]

Slightly different method to Stinkwheel

Although I guess I lose marks for not using a ruler
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[qarka]

[stinkwheel]

You would ordinarily measure the 200 metres from the base of the wall then measure the angle (x) to the top of the building.

tan x = height/200

Not always possible to measure the distance from the base of the wall though because other buildings may be in the way and you can only get a line of sight from certain locations.

If you're stood on site with a theodolite, a mape measure and a calculator and you have to call a mate to work out the height of a building on a CAD package. The foreman is going to give you the sack.

I'm a believer in maths having a purpose though and for the people doing it to be aware of that purpose. Especially at lower levels. Someone doing an HNC in construction shouldn't have problem knowing exactly why you'd want to do that calculation. The question posted should be well within the reach of someone doing GCSE/Standard grade maths but at that level I might have worded it differently. Maybe something like this:
https://i48.photobucket.com/albums/f216/stinkwheel/baddesley-clinton-solihull-gb939.jpg
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.