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to check if square

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Oct 11, 2013, 11:23 PM
to check if square
i am trying to remember the way to check two sides if they are square.. i belive you would do 3 on one and 4 on the otherside then check diagonally it should end up with the number 5,, am i right or wrong on this formula ??
Oct 11, 2013, 11:43 PM
If you're checking for a 90 degree angle, that would be the basic numbers to use. But if you have room, I would go with 6 8 10. And that checks for 90 degree angles.

If you want to check if a rectangle is not lopsided, then cross measure and they should be equal. Or you will have to shove one side or another as needed. If one measurement is 98 inches, and the other one is 96 inches, then figure out which way you need to shove it and do it 1 inch. Then remeasure.

This message has been edited. Last edited by: Re-mdlr,

They make it look so easy on tv, don't they
Oct 11, 2013, 11:45 PM
jimbo4dog, If you're checking to make sure you have a 90 degree corner, then, yes you have the formula correct. The Pythagorean theorem says, for a right triangle, a^2 + b^2 = c^2
So, if "a" is 3, "b" is 4 then 3^2 + 4^2 = 9 + 16 = 25 which equals 5^2

But, as someone who never seems to get things as level or square as they should be, I'd probably use a corner square.
Oct 12, 2013, 01:22 AM
The framing square is a good start, but measuring a larger distance is more accurate.

As said above: From one corner, measure 3' along one edge. Then, from the same corner, measure 4'along the other side of the square. Measuring a diagonal between those two points should be 5' if the corner is square. Works the same (only even more accurate) if you measure 6-8-10.

Oct 12, 2013, 09:20 AM
thanks for all your inputs,, i thought i was lossing my mind,,haha. have a great day !!