A Middle-School Math Trick You'll ACTUALLY USE

Want to know how to check literally ANYTHING for square? From small projects, to houses, to fields, the 3-4-5 squaring trick just plain works. Here I show you not only how to do the 3-4-5 rule but how to figure out what to do next if you are out of square.

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[GrantOakes]

I LOVE your simple approaches to many wood crafting issues! Pleas, keep them coming, I LOVE your channel!

[glencrandall]

Thank you for sharing. Well known information but often forgotten. Good refresher. 🙂🙂

[markhopkins]

Again, thanks for sharing something I'm sure was taught in school when my attention span was less than an INCH! So appreciate your content. Thanks again for sharing

[mattmayes]

Thank you sir for showing us another good option checking for square. This past weekend I was checking for square on some leftover plywood that was longer than my Woodpecker square. I thought to use a level with it to extend the reach.

[lincolndickerson]

I love geometry in the workshop. Makes so many things simple.

[jethropebs]

Brilliant, and as usual, I totally enjoy your patient, clear, and concise teaching method. Thanks for the tip!

[skippylippy]

That's neat! Thanks for sharing this trick. 👍

[awlthatwoodcrafts]

I used this on my first project, building an enclosure for a bearded dragon. I was using melamine. I only had a circular saw at the time and I bought one of those Empire edge guides from HD to assist me in cutting a straight line. I needed to make sure that all of my pieces were square so I used the 3-4-5 rule to make sure. It worked great.

[michaelnorman]

Feel like I’m always disappointed in that scenario, just striving to be better at that.thanks for sharing this it has helped me do better! Thanks

[rogersanders]

Great tip. I've known this one since high school trig class. It is extremely accurate too, especially as you scale it up to say a porch or room layout. Maybe you can do a follow up showing how accurate this method is.

[jonathanphares]

Another great response for the age old question of "When am I going to use this math in the real world?"! Nice job!

[stefanr]

the 3 to 4 to 5 rule is easily get done with a folding ruler. one side 120cm, the other side 160cm and the hypothenuse have to be exactly 200cm, measured from edhe to edge of the folding ruler.
greets Carpenter from germany

[BobBlarneystone]

A long time ago, I learned to use the information printedon a framing square to lay out many angles. I don't think I remember much of it now, but the 3-4-5 triangle has stuck with me. I still use the trigonometric functions on a slide occasionally, as well as for arithmetic calculations. It's still the original solar powered calculator.

[JamesSmullins]

Used that a lot back when I was a commercial electrician and had to lay out rooms with string to know exactly where to bring up pipes for panels. You could verify the room was laid out square even before the pad was poured.

When all you've got are batter boards (badder?) to measure from you have to know how to insure your layout for stub ups is perfect.

[wjim]

The Pythagorean Theorem is the only algebra I ever used since high school!

[steveferguson]

I’ve used this method for years. Great video

[MCsCreations]

Excellent tip, dude! Thanks!!! 😊
Stay safe there with your family! 🖖😊

[TheCankersore]

Thanks for the tip. FYI, another 2 sets of numbers to keep in mind like 3-4-5 are 12-16-20 & 15-20-25.

[carlmclelland]

Another one that works well, for 45 degree angles is 1, 1, square root of 2 (1.414). I use that for many measurements, but one must remember, it's using decimal increments instead of fractions.

[regularguy]

Personally I’m a fan of the 5-12-13 rule, or the 7-24-25 in a pinch!