To find the perimeter of a triangle, you add together the lengths of all three sides. The formula is: Perimeter = a + b + c where aaa, bbb, and ccc are the lengths of the sides of the triangle
Steps to find the perimeter:
- Measure the lengths of all three sides of the triangle, ensuring they are in the same unit.
- Add these lengths together.
- The sum is the perimeter, expressed in the same unit as the side lengths.
Special cases:
- For an equilateral triangle (all sides equal), the perimeter is simply 3×a3\times a3×a, where aaa is the length of one side
- For a right triangle where one side is unknown, you can use the Pythagorean theorem to find the missing side before adding all sides to get the perimeter
- If you know two sides and the included angle (SAS), you can use the law of cosines to find the third side, then sum all sides for the perimeter
In summary, the perimeter is the total distance around the triangle, found by summing the lengths of its three sides.
