garden fence at right-angle to house

[dpb]

HeyBub wrote: ...

Wow!!! By "several decades"????!!!! That long. Who'da thunk it? :)

--

[Harry Stottle]

It does if the original rectangular 'old door', or sheet of 6' x 2' chipboard, has perfectly squared corners, but 1/2 an inch out and it could result in land grab ;-)

[John]

Right angles (and every other angle) have been around forever, it's just that nobody named them. Same as gravity, space, oxygen, grass, ocean, sky, etc. etc.

See above. There has been at least two circles from the day man was 'born', and he saw them every day, the sun and the moon

Cheers

John

[unow]

Not to mention the circle that "man" was born out of.

[Jeff]

Peter Bruells wrote in news: [e-mail]:

The Egyptians could have got right angles without using math. Lay out a rectangle and measure that the opposite corners in each direction are the same distance.

[Tim Smith]

Let's say the corners, in order, as you traverse the perimeter of the "rectangle" are A, B, C, and D. What do you mean by "opposite corners"? At first, I'd take that to mean A and C are opposite corners, and B and D are opposite corners. But then AC and BD can be the same distance, without the thing actually being a rectangle:

A B +----------------+ / \\ / \\ / \\ +------------------------+ C D

To ensure that a four-sided convex plane figure is a rectangle, I think we need to check all of these:

AB = CD AC = BD AD = BC

Here's a simple way to get a right angle. Let's say we want a right angle to this wall:

| | +-----------------------------*-------------------------------+

We want a right angle at the point marked with the asterisk. We need two pieces of string, the same length, each marked about 1/3 of the way from one end. The marks should be in the same position on each string. The end farthest from the mark should be attached to a stake or something, so that it can be driven into the ground. I'll draw the string like this:

.....o........v

The v represents the stake, and the o is the mark 2/3 from the free end.

Lay out one of the strings against the wall, with the mark at the * point, and drive the stake into the ground:

| | +-----------------------------*-------------------------------+ .....o........v

Move that string out of the way, and then place the other string's mark at the *, but with the stake going toward the other direction, and drive its stake in:

| | +-----------------------------*-------------------------------+ v........o..... v / / .....o

At this point you have two stakes driven into the ground on opposite directions along the wall from the * point, but the same distance from it, and each stake has a string attached to it. The strings are the same length. Now just bring the ends of the two strings together and pull them both taught (these drawings are distorted due to the limitations of ASCII art and how much time I'm willing to try to make it):

| | +-----------------------------*-------------------------------+ v v \\ / \\ / \\ / o o \\/

A line from the place where the ends of the strings meet, to the *, is perpendicular to the wall.

Note that this construction is based on the classic geometry problem of constructing a perpendicular to a line.

[AJH]

You have gone very quiet John. What do you think so far then ?!

[john westmore_______]

after my nervous breakdown trying to keep up with these posts, i'm going into therapy, selling the house, and moving to alaska

[gavin]

Watch the film "Into The Wild" first :-)

[john westmore_______]

just read an account on which the film is based. Yipes.....please change alaska to london u.k.

[Smitty Two]

A god-awful insult of a movie anyway, of an arrogant, misanthropic teenager trying to find his way out of upper middle class suburban boredom.

The guy was stupid, blowing around in the wind in a totally brainless emotional psuedo-quest, making idiotic decisions at every juncture. The screenplay was abominably constructed, too, with no character development and scene after scene of random useless filler.

I cared so little for the character in the movie that it's hard to even feel any compassion for the joker who pulled the pathetic stunt in real life.

[The Real Bev]

I felt sorry for his parents, who loved him even if he was a jerk. And then, of course, there's 'Grizzly Man'.