Armed Polite Society
August 19, 2019, 05:27:02 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News:
 
   Home   Help Search Login Register  
Pages: [1] 2
  Print  
Author Topic: Math actually works!  (Read 335 times)
castle key
friend
Senior Member
***
Posts: 522


« on: August 13, 2019, 01:26:39 PM »

I am laying out a construction project, a bocce court. The basic gist is a 10 foot by 60 foot outline with poles every ten feet. These poles will have overhead stuff to create a pergola.

I pondered laying out an accurate right angle at the corners and had that "aha moment" that I could set marks for the 60' line, mark off ten foot increments for each of the poles, and as the width was equal to the run to the first mark, the hypotenuse was my answer!

Of course, I couldn't remember the formula, but a quick search gave the answer.

And I thought I would never use geometry again after middle school.

Mrs. Castle Key and I decided that few of today's children would have any clue how to do this simple calculation or even where to begin trying. I weep for our future.
Report to moderator   Logged

Vigilate hoc, tenendum per ebrietatem.
WLJ
friends
Senior Member
***
Posts: 2,314


Currently on patrol in the Epsilon Eridani System


« Reply #1 on: August 13, 2019, 01:51:00 PM »

But AOC says math = free
Report to moderator   Logged
Mike Irwin
friend
Senior Member
***
Posts: 30,016


I Am Inimical


« Reply #2 on: August 13, 2019, 02:40:18 PM »

3, 4, 5

Sent from my SM-G960U using Tapatalk
Report to moderator   Logged

Carbon Monoxide, sucking the life out of idiots, 'tards, and fools since man tamed fire.
230RN
friend
Senior Member
***
Posts: 13,132


You can't have a republic without an honest media.


« Reply #3 on: August 13, 2019, 06:03:15 PM »

Obligatory:

https://en.wikipedia.org/wiki/The_Feeling_of_Power

I've noticed that with a person of considerable mechanical skills.  In determining tailstock setover for a cut of a given angle, he'd rather resort to the internet or CAD system than use the actual math concepts.

Fun, classic:

    

^ Also obligatory.

Heaven help us if the internet ever collapses totally.

Terry, 230RN

Slooshun:

In the trigonometric identity:

 sin(θ) ¸ cos(θ) = tan(θ)

Subsituting the variable "gerine" for theta, we get:

sin(gerine) ¸  cos(gerine)  = tan(gerine)

Image credit in properties.
« Last Edit: August 13, 2019, 06:39:02 PM by 230RN » Report to moderator   Logged

"Equality" in our system of government only means equality of opportunity and equal protection under the law.  It does not mean, nor does it mandate, numerical identity in all things between all people.
French G.
friend
Senior Member
***
Posts: 7,859


ohhh sparkles!


« Reply #4 on: August 13, 2019, 06:45:16 PM »

I would set the four corners first, make sure you have your ten and sixty as close as you can, then just measure corner to corner. If the measurement is the same then you have a good rectangle, no matter what that measurement is. I cough up a hypotenuse every now and then welding when I have no other way to check square, but use corner to corner daily. Once the corners are good do everything else on a string line.
Report to moderator   Logged

AKA Navy Joe   

I'm so contrarian that I didn't respond to the thread.
Hawkmoon
friend
Senior Member
***
Posts: 20,155



« Reply #5 on: August 13, 2019, 08:34:24 PM »

I am laying out a construction project, a bocce court. The basic gist is a 10 foot by 60 foot outline with poles every ten feet. These poles will have overhead stuff to create a pergola.

I pondered laying out an accurate right angle at the corners and had that "aha moment" that I could set marks for the 60' line, mark off ten foot increments for each of the poles, and as the width was equal to the run to the first mark, the hypotenuse was my answer!


I don't understand what you did, but I'm not going to admit it.
Report to moderator   Logged
castle key
friend
Senior Member
***
Posts: 522


« Reply #6 on: August 14, 2019, 02:28:46 AM »

I would set the four corners first, make sure you have your ten and sixty as close as you can, then just measure corner to corner. If the measurement is the same then you have a good rectangle, no matter what that measurement is. I cough up a hypotenuse every now and then welding when I have no other way to check square, but use corner to corner daily. Once the corners are good do everything else on a string line.

I sort of did that, but I don't think you can really set all four corners by eye and get them square.

I set one long run, a sixty footer, and pulled a line. That side would be straight. I then did the ten foot measurements, which is manageable and a good start to get the square. Am I missing something from your thoughts to set four corners and then nudge it around a bit?

The real fun will be setting the 6 x 6 uprights and getting them accurately in line. Those are big "logs" over a long run. Thoughts?
Report to moderator   Logged

Vigilate hoc, tenendum per ebrietatem.
dogmush
friend
Senior Member
***
Posts: 7,401


« Reply #7 on: August 14, 2019, 05:05:29 AM »

When I used to set a long line of fence posts we'd just use a level and a string.  Bring the outside face to the string line and make sure it's vertical.

Report to moderator   Logged
French G.
friend
Senior Member
***
Posts: 7,859


ohhh sparkles!


« Reply #8 on: August 14, 2019, 06:03:23 AM »

If four points measure the same across the diagonals the only possibilities are you built a rectangle or a trapezoid. And if your sixty and ten are correct, then you are there. I think you came out fine, similar method in steps. Now the real question, how the hell do you play bocce?
Report to moderator   Logged

AKA Navy Joe   

I'm so contrarian that I didn't respond to the thread.
HeroHog
Gimpy Old Pharte, Formerly Jussie Smollett.
Administrator
Senior Member
*****
Posts: 5,445


It can ALWAYS get worse!


WWW
« Reply #9 on: August 14, 2019, 06:18:10 AM »

All I remember is a^2+b^2=c^2
Report to moderator   Logged

I might not last very long or be very effective but I'll be a real pain in the ass for a minute!
MOLON LABE!
230RN
friend
Senior Member
***
Posts: 13,132


You can't have a republic without an honest media.


« Reply #10 on: August 14, 2019, 06:46:25 AM »

a is not square, a is cool.

(Dredged up from the few remaining memories of high school.)
Report to moderator   Logged

"Equality" in our system of government only means equality of opportunity and equal protection under the law.  It does not mean, nor does it mandate, numerical identity in all things between all people.
HeroHog
Gimpy Old Pharte, Formerly Jussie Smollett.
Administrator
Senior Member
*****
Posts: 5,445


It can ALWAYS get worse!


WWW
« Reply #11 on: August 14, 2019, 06:50:41 AM »

Pie arn't square, boy, pie are round, cornbread (sweet) are square!
Report to moderator   Logged

I might not last very long or be very effective but I'll be a real pain in the ass for a minute!
MOLON LABE!
Hawkmoon
friend
Senior Member
***
Posts: 20,155



« Reply #12 on: August 14, 2019, 07:09:11 AM »


I set one long run, a sixty footer, and pulled a line. That side would be straight. I then did the ten foot measurements, which is manageable and a good start to get the square. Am I missing something from your thoughts to set four corners and then nudge it around a bit?


What you missed is where French G. mentioned putting in all four corner posts and comparing the diagonal measurements. Putting in two corners and the intermediate ten-foot points only gives you a line, not a rectangle. The intermediate ten-foot points don't do anything to help make the corners 90-degrees.
Report to moderator   Logged
bedlamite
Hold my beer and watch this!
friend
Senior Member
***
Posts: 6,926

Ack! PLBTTPHBT!


« Reply #13 on: August 14, 2019, 07:14:14 AM »

Pie arn't square, boy, pie are round, cornbread (sweet) are square!

That's just your opinion. But without pi, it's just an onion.
Report to moderator   Logged

A plan is just a list of things that doesn't happen.
AZRedhawk44
friends
Senior Member
***
Posts: 12,169



« Reply #14 on: August 14, 2019, 07:20:03 AM »

3, 4, 5

Sent from my SM-G960U using Tapatalk

Nope.  that's for a 30-60-90 triangle, if I remember correctly.

He's looking for an equilateral right triangle.  90-45-45.

That is 1, 1, sqrt(2).

Given a 60x10 rectangle and support posts every 10 feet along the 60 foot side, you would have a series of 10x10 squares all in a row:

|=|=|=|=|=|=|

The hypotenuse of one section (|=|) is of a 10x10 square.

|\|

a^2 + b^2 = c^2.

100 + 100 = c^2

c = sqrt(200) = 14.14 feet.

All that assumes I understood the correct hypotenuse you were looking for.


ETA:  A 3/4/5 triangle evidently doesn't have 30/60/90 degree angles.  They're odd numbers.
Report to moderator   Logged

"But whether the Constitution really be one thing, or another, this much is certain - that it has either authorized such a government as we have had, or has been powerless to prevent it. In either case, it is unfit to exist."
--Lysander Spooner

I reject your authoritah!
bedlamite
Hold my beer and watch this!
friend
Senior Member
***
Posts: 6,926

Ack! PLBTTPHBT!


« Reply #15 on: August 14, 2019, 07:29:19 AM »

3,4,5 triangle has angles of about 53.1, 37.9, and 90.

Why do I even remember that? Nevermind, I don't want to know.
Report to moderator   Logged

A plan is just a list of things that doesn't happen.
castle key
friend
Senior Member
***
Posts: 522


« Reply #16 on: August 14, 2019, 08:27:37 AM »

Once I get the verticals set and and installed, I will need to place horizontal cross pieces at the tops. These need to all come out level. Further, I need to grade the ground and put in the surface, which will be about 8-10 inches deep, and must be level.

I was thinking of using a laser level to mark all of my points. What think you all?

If a laser is the suggestion, please suggest brands/tools, understanding that I don't really want to spend a gazillion dollars. Point lasers, rotary lasers, green/red? The measurement run will be about 60 feet.
Report to moderator   Logged

Vigilate hoc, tenendum per ebrietatem.
AZRedhawk44
friends
Senior Member
***
Posts: 12,169



« Reply #17 on: August 14, 2019, 09:01:31 AM »

I'd say just use a good long beam level on each support.

Put your vertical footers in concrete blocks like this:

https://www.homedepot.com/p/7-3-4-in-x-10-1-2-in-x-10-1-2-in-Concrete-Pier-with-Strap-Block-100002710/100321949

Level the blocks by adding sand under the low ones.

Then haul in your substrate for your ground (is it rock?  sand?  Not familiar with bocce ball play conditions).  Fill even with the concrete blocks and they won't slide around anywhere.
Report to moderator   Logged

"But whether the Constitution really be one thing, or another, this much is certain - that it has either authorized such a government as we have had, or has been powerless to prevent it. In either case, it is unfit to exist."
--Lysander Spooner

I reject your authoritah!
grampster
friend
Senior Member
***
Posts: 8,194



« Reply #18 on: August 14, 2019, 09:01:36 AM »

 sin(θ) ¸ cos(θ) = tan(θ)

sin is doing it on the beach.   The cos(t) does equal a tan if the sin is during the day.  It also leads to skin cancer. Grumpy Old Man
Report to moderator   Logged

"Never wrestle with a pig.  You get dirty, and besides, the pig likes it."  G.B. Shaw
bedlamite
Hold my beer and watch this!
friend
Senior Member
***
Posts: 6,926

Ack! PLBTTPHBT!


« Reply #19 on: August 14, 2019, 09:04:42 AM »

 sin(θ) ¸ cos(θ) = tan(θ)

sin is doing it on the beach.   The cos(t) does equal a tan if the sin is during the day.  It also leads to skin cancer. Grumpy Old Man

Don't be so obtuse.
Report to moderator   Logged

A plan is just a list of things that doesn't happen.
Mike Irwin
friend
Senior Member
***
Posts: 30,016


I Am Inimical


« Reply #20 on: August 14, 2019, 04:18:00 PM »

3, 4, 5 gives a perfect right angle.

Multiple them by the same number, any number, and you get a right angle.

Using that to set your baselines you can lay out any number of sections of equal dimension.

Sent from my SM-G960U using Tapatalk
Report to moderator   Logged

Carbon Monoxide, sucking the life out of idiots, 'tards, and fools since man tamed fire.
AZRedhawk44
friends
Senior Member
***
Posts: 12,169



« Reply #21 on: August 14, 2019, 06:16:44 PM »

3, 4, 5 gives a perfect right angle.

Multiple them by the same number, any number, and you get a right angle.

Using that to set your baselines you can lay out any number of sections of equal dimension.

Sent from my SM-G960U using Tapatalk

Yes it does, but not for a 10' x 10' triangle.

His dimensions between posts is 10x10.  To ensure all corners are square, the diagonals of a 10x10 square must be sqrt(200), or about 14.14 feet.

3/4/5 doesn't matter here.  Different triangle, different relationship.
Report to moderator   Logged

"But whether the Constitution really be one thing, or another, this much is certain - that it has either authorized such a government as we have had, or has been powerless to prevent it. In either case, it is unfit to exist."
--Lysander Spooner

I reject your authoritah!
zxcvbob
friend
Senior Member
***
Posts: 8,555



« Reply #22 on: August 14, 2019, 06:28:10 PM »

Yes it does, but not for a 10' x 10' triangle.

His dimensions between posts is 10x10.  To ensure all corners are square, the diagonals of a 10x10 square must be sqrt(200), or about 14.14 feet.

3/4/5 doesn't matter here.  Different triangle, different relationship.

Not really.  Lay out a 9x12x15 triangle to set the angle.  Shorten the 12 and extend the 9 to get the dimensions you really want.  If you don't think you can lengthen a side and keep it straight, stake out 12x16x20 and then measure 10 feet in each direction from the corner.
Report to moderator   Logged

"It's good, though..."
AZRedhawk44
friends
Senior Member
***
Posts: 12,169



« Reply #23 on: August 14, 2019, 07:42:39 PM »

Not really.  Lay out a 9x12x15 triangle to set the angle.  Shorten the 12 and extend the 9 to get the dimensions you really want.  If you don't think you can lengthen a side and keep it straight, stake out 12x16x20 and then measure 10 feet in each direction from the corner.

I completely grok that 3/4/5 is extensible to 6/8/10, 9/12/15, 27/36/45 ad infinitum.

Castle key wants a rectangle that is 10x60, segmented into 6 adjoining 10x10 squares, and to ensure that all square segments are perfectly square with 90 degree angles.

For a given 10x10 enclosure, you ensure that the corners are square by measuring the diagonals of the square.  Those diagonals create an isosceles right triangle.

If the diagonal from top left to bottom right is the same length as the diagonal from bottom left to top right, then you have a properly squared structure.

|\| = |/|

If those two diagonals are not equal, you don't have a square... you have a rhombus or a trapezoid or an irregular 4-sided structure.  But it ain't a square.

In the case of a 10x10 square, 3/4/5 has no relationship at all... but there is a well documented relationship similar to 3/4/5 that pertains to isosceles right triangles:  1/1/sqrt(2).

https://www.themathpage.com/aTrig/isosceles-right-triangle.htm
Report to moderator   Logged

"But whether the Constitution really be one thing, or another, this much is certain - that it has either authorized such a government as we have had, or has been powerless to prevent it. In either case, it is unfit to exist."
--Lysander Spooner

I reject your authoritah!
zxcvbob
friend
Senior Member
***
Posts: 8,555



« Reply #24 on: August 14, 2019, 10:21:49 PM »

I completely grok that 3/4/5 is extensible to 6/8/10, 9/12/15, 27/36/45 ad infinitum.

Castle key wants a rectangle that is 10x60, segmented into 6 adjoining 10x10 squares, and to ensure that all square segments are perfectly square with 90 degree angles.

For a given 10x10 enclosure, you ensure that the corners are square by measuring the diagonals of the square.  Those diagonals create an isosceles right triangle.

If the diagonal from top left to bottom right is the same length as the diagonal from bottom left to top right, then you have a properly squared structure.

|\| = |/|

If those two diagonals are not equal, you don't have a square... you have a rhombus or a trapezoid or an irregular 4-sided structure.  But it ain't a square.

In the case of a 10x10 square, 3/4/5 has no relationship at all... but there is a well documented relationship similar to 3/4/5 that pertains to isosceles right triangles:  1/1/sqrt(2).

https://www.themathpage.com/aTrig/isosceles-right-triangle.htm

I understand what you're saying; did from the start.  And checking that the diagonals are equal is the sanity check to make sure your box is rectangular.  But you can use a 3/4/5 triangle to lay out the first right angle; (maybe you're in the field and can't remember the square root of 2  rolleyes) none of the sides have to be divisible by 3.  Mark off 3x from the corner in one direction, 4x in the other direction, and make sure the segment connecting those is 5x.

Once he has the 60' side staked out, put a flag every 10 feet.
Report to moderator   Logged

"It's good, though..."
Pages: [1] 2
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!
├ťmraniye escort ankara escort Kartal Escort ata┼čehir escort pendik escort ┼či┼čli escort kurtk├Ây escort ankara escort ankara escort avc─▒lar escort istanbul travesti escort bayan escort avc─▒lar escort antalya escort ankara escort t├╝rk porno t├╝rk porno Halkal─▒ Escort Bayan ─░stanbul Escort Etiler Escort taksim escort maltepe escort Ankara Escort ├çankaya Escort Eryaman Escort Etiler Escort Bayan Rus porno Eros Porno Bah├že┼čehir Escort Ankara escort bayan Sincan Escort Bayan Ankara escort Maltepe Escort Etlik Escort Beylikd├╝z├╝ Escort Kurtk├Ây Escort Demetevler Escort Antalya escort Bodrum Escort Bayan ┼×i┼čli Escort Escort ─░zmir Kurtk├Ây Escort Ankara Escort ├ťmraniye Escort ankara escort Ankara Escort Bayan Keci├Âren Escort Escort Ankara porno altyaz─▒ Kad─▒k├Ây Escort Escort bayanlar Escort ankara Ankara Escort Bayan Kurtk├Ây Escort Beylikd├╝z├╝ Escort Kurtk├Ây Escort ┼×irinevler Escort Antalya Escort Escort Mersin Taksim Escort Bayan Escort beylikd├╝z├╝ Beylikd├╝z├╝ Escort Bakirkoy Escort Atak├Ây Escort Bah├že┼čehir Escort istanbul escort Ankara escort Ankara Escort Altyaz─▒l─▒ Porno mecidiyek├Ây escort Escort izmir Altyaz─▒l─▒ Porno Esenyurt Escort