If laying out square lines is part of your next home improvement project, here’s a great way to do it using the Pythagorean theorem (A² + B² = C²) to form a right angle triangle with 3′ and 4′ sides and a diagonal of 5′:

  1. Establish a 4′ line parallel to a wall.
  2. Measure out 3′ from one end of the 4′ line roughly perpendicular to it.
  3. Hold a tape measure on the other end of the 4′ line.
  4. Measure 5′ so it forms a triangle with the end of the 3′ line.
  5. Adjust the angle of the 3′ line until the tape measure aligns with it.

Watch the video above to find out more.

Editorial Contributors
avatar for Joe Truini

Joe Truini

Radio Show Co-Host

Joe Truini is a contractor, author, and the host of “Simple Solutions” on Today’s Homeowner TV and the weekly Today’s Homeowner radio show. He has worked on both large commercial projects and residential remodeling, and has written for national publications such as This Old House and Popular Mechanics. He has also written eight books, including three best-selling shed-building books. Joe lives in Connecticut with his family and enjoys hiking, traveling, and baseball in his spare time.

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