What is the formula to figurwe out the distance of the blue line? Thanks.
Posted by Rodger MacMunn (Member # 4316) on :
I think you need one more number to use the Pythagoream theorum, but drawing it to scale gives me about 218'. Geometry was a L O N G time ago ......
Posted by Ian Stewart-Koster (Member # 3500) on :
The formula is the ratio of the length of 2 of the sides to each other, equals the other ratio of the lengths of the 2 sides which include the unknown.
Longside2, the long side of the new triangle is (755-260)= 495
So 262/755 = Blueline/495
So Blueline = 262/755 x 495 = 171.77 ft or 171' 9-1/4"
(unless I made a mistake!)
[ September 18, 2013, 07:48 AM: Message edited by: Ian Stewart-Koster ]
Posted by Rick Sacks (Member # 379) on :
172
[ September 18, 2013, 10:12 AM: Message edited by: Rick Sacks ]
Posted by Kelly Thorson (Member # 2958) on :
Thanks!!!
Posted by Dan Beach (Member # 9850) on :
You can just draw this to scale and measure it as well.
Posted by old paint (Member # 549) on :
what is the extended "diamond" shape for? if you can find the ends of the "hypothesis", iam assuming this is land, get a big ball of string secure it at one point in the middle of the road, roll it out till you get to the other one, come down on the vertical......and measure in toward the hypothesis........sort trial and error.... till you get the 260'. or hire a surveyor what has a piece of equipment like this or buy one: http://www.engineersupply.com/Bosch-Laser-Distance-Measurer-GLR825.aspx Posted by Ricardo Davila (Member # 3854) on :
Be careful.....the street that appears perpendicular, in the graphic, seems to be narrower than the street that runs horizontally.......Thus, the centers of each road are going to be in a different position.....Make sure that you measure the width of each one of those roads, before you apply your measurements into your equation.
NUMBER TWO: If everything else fails, and the degree of accuracy needs to be on target, get a helper and measure the distances with a 50 FT. measuring tape.....Since, it appears that you will be measuring a length of approximately 172 ft, more or less, it will only take three ( measures of 50ft, each, and one of 22ft.....In my opinion, if accuracy is needed, this is the way to go.
RD
Posted by Ian Stewart-Koster (Member # 3500) on :
For an architectural drawing, it is atrocious in clarity. It looks like they have labelled what I guess is the land as a road... or is that typical of architects? Posted by Kelly Thorson (Member # 2958) on :
It's a site triangle for the department of highways. No signs can obstruct the view of a highway from a secondary road. I did draw it to scale in Corel Draw, but then when the client wanted to know where they could put the sign if they moved it one direction or other. If I have a formula we can figure it out right on site. I think what I will do is figure out a few points and run a string between them and then tell them it can be anywhere behind that string. Once we decide where they want it I will measure again from the center point of each road to be sure. We are pouring a 1.5 cu yd concrete pad and the sign will be permanently mounted to it so there is no room for error. I thought I had it dialed in and then my figures I had been working with were not jiving. Turns out there are different sized site triangles for different speed limit zones. Makes sense I guess, but all the measurements I had figured out from my scale drawing were no good. Once all that is figured they can apply for the permit, it's just easier to be involved in this than deal with the fallout when it isn't done right - or at all as in this case. Posted by Kelly Thorson (Member # 2958) on :
quote:Originally posted by Ian Stewart-Koster: For an architectural drawing, it is atrocious in clarity. It looks like they have labelled what I guess is the land as a road... or is that typical of architects?
In all fairness it is actually a crop of the drawing so if I had posted the entire thing it is better explained.
Posted by Dennis Kiernan (Member # 12202) on :
The problem seems very simple and I think Ian nailed it.
It's the same as reducing a large rectangle to a smaller one keeping the same proportions between the height and the width.
Isnt it?
Posted by Rick Sacks (Member # 379) on :
Dennis, that certainly simplifies it! We don't need to look at triangles at all.
775 minus 260=495 So if I reduce it to a length of 495 holding the same proportions, I get 171.775
Thank you Dennis
Posted by Don Coplen (Member # 127) on :
I got 171.775 also.
This can't be math...it was kinda fun.
Posted by jack wills (Member # 521) on :
IOAFS...
Posted by Don Coplen (Member # 127) on :
Jack, more likely IOAFSP.
(sign permits are often PITA)
Posted by Kelly Thorson (Member # 2958) on :
Thanks everyone, site prepped and concrete is on it's way!
Posted by old paint (Member # 549) on :
and she wont tell us what the right dimension was........
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