How to Find the Perimeter of a Right Triangle

Measuring to Find Perimeter

A right triangle has three sides, just like every other triangle. What makes a right triangle different is that one of its corners has an angle of 90 degrees. Once you've identified your right triangle, you can begin to measure it. Every triangle, including the right triangle, has a perimeter, which is the combined measurement of all of its sides. With the correct formula and accurate measurements, you can find the perimeter of a right triangle in hardly any time at all.

Things You'll Need

• Right triangle
• Ruler
• Calculator

Instructions

1. Label each side of the right triangle. Something as simple as A, B and C will work just fine. You just want to make sure that you're not adding the same side twice in the upcoming equation.

2. Measure each side of the triangle. Adjust the units of length depending on the size of the triangle. For example, if you are measuring a small triangle, measuring it in millimeters might give you the most accurate results.

3. Plug the measurement of each side of the right triangle into this equation: Perimeter = A+B+C.

4. Add up the three sides using a calculator. The sum of the three sides will equal the perimeter of the right triangle.

References

• AJ Designs Software: Triangle Equations Formula Calculator