Extra: The puzzle presented in this activity is called a “perimeter magic triangle of order three.” To extend it to a higher-order perimeter magic triangle start by drawing a new triangle.

This KS2 maths article explains how perimeter is the distance around a 2D shape and how to work it out on a grid.

Any triangle has between one and three lines that bisect both the area and the perimeter. We determine the conditions for each possible number. The College Mathematics Journal emphasizes the first two ...

A triangle is a closed shape with three sides and three vertices. The general formula to calculate the area of a triangle is half of the product of its base and height.