My maths sucks, can you help OCUK?

Soldato
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From my quickly drawn diagram can anyone tell me what legnth X is?

idunnork2.gif


Yes, the blue thing is a rectangle, as is the orange thing, so they've got nice 90* angles. There is probably some trigonometry thing I gone for my GCSE's to work this out, but I cant remember it. :o :(

Ty if you can help. :)
 
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Not really :)

But the solution will almost certainly involve working out the lengths of the two small blue triangles at each end of the ruler, using these to subtract from the length of the rectangle will let you work out the length ofthe large blue triangles ach side of the ruler.

I'm guessing trig to work out the little trangles (as you only have one length) and pythagorus to work out the length of the ruler (hypotonus) once you have the lengths worked out.
 
yeh use pythagorous to work out the length of the little end bits and subtract that from the 205 and the 260 to get lengths, then a squared + b squared = x squared. work tht out then square root to get X.

if tht methods correct, i think it is.. then i got X to be 271.6cm to 1dp.
 
Just noticed this is your diagram - what form does the actual question take? Did it have a picture, i so did you leave anything off? Also what did the question say?
 
best guess is 273.11 cm.

[edit] ohh and the little triangles at the ends of the block don't have equal lengths, this would only be if the surrounding object was a square.
 
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Nvm, got it. 274cm it should be. I think.

Just drew it to 1:10 scale in Publisher, printed it, then got a ruler out. :D

Telescopi said:
Just noticed this is your diagram - what form does the actual question take? Did it have a picture, i so did you leave anything off? Also what did the question say?

Customer doddled in and wants a big "CLEARANCE SALE" banner 60cm deep, to go across their 260 x 205cm window, diagionally. :p

Hmm.....everyone seems to be getting smaller than that. I'll play it safe and do it 270cm.
 
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elitetrick said:
no telescopi the little ends are a right angled triangle, 2 sides of equal length... as other 2 angles are 45 degrees if its a rectangle inside a rectangle tht has to make 45. so u get 60 as hypotenuse then other 2 sides should be same length, it turns into decimals

Nope, they aren't the same.

BUT...

I predict that length a on one end of the ruler will equal length b on the other and vice versa, if thats any help to anyone :)
 
Le_Petit_Lapin said:
Nvm, got it. 274cm it should be. I think.

Just drew it to 1:10 scale in Publisher, printed it, then got a ruler out. :D



Customer doddled in and wants a big "CLEARANCE SALE" banner 60cm deep, to go across their 260 x 205cm window, diagionally. :p

Hmm.....everyone seems to be getting smaller than that. I'll play it safe and do it 270cm.


Ahh, you didn't say it was a real problem, in that case your solution is the best, only ever use maths for school :)
 
titaniumx3 said:
Problem is the picture seems very inaccurate. At the top right corner, the orange rectangle is popping out a bit.

Its not supposed to be popping out a bit. It was a very quickly drawn picture, and isnt very accurate. :o
 
I don't think it is possible, you need to know the diemnsions of the small blue triangles in the corners to calculate.
 
I get 301.6 using trig then Pythagoras.
and now my head hurts as its been so long since ive used maths! :o
 
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my drawing skills are fairly useless, but i'll try to explain.

as the bottom edge of the orange block will run parellel to the diagonal from the bottom left to top right of the rectangle, trig will tell that the angle the diagonal line of the rectangle will be 38.25 degrees.

so the internal angle of the bottom right corner of the small triangle on the left will be 90 - 38.25, trig again will give you the two side of a small triangle with using 60 as the hyp, so the bottom of a small triangle is 37.15, and the height is 47.11.

so using pythag, bottom of large triangle is 260-37.15 and height is 205-47.11, it gives the length of X as 273.11

(although i could be wrong, like a lot of the spelling i guess)
 
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i'll go back to my cold quiet corner once more and wait for the time the world needs sup3r-n3rd. if only i'd thought of drawing it in visio, it would have calculated for me exactly.
 
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