On the paper with the triangle use the 21 pennies to build towers on each circle. ... To extend it to a higher-order perimeter magic triangle start by drawing a new triangle.

Area of Triangle Formula: In general, "area" refers to the region inside the boundary of a flat object or figure and is measured in square units, with the standard unit being square meters (m²).

The length of the first triangle was 1 square. You have to multiply this by a scale factor ... add up all four sides to find the perimeter. Two sides are 21cm and two sides are 36cm. 21 + 36 + 21 ...

In this National 4 Lifeskills Maths study guide, you can revise how to find the perimeter and area of triangles, quadrilaterals (rectangle, parallelogram, rhombus, kite and square), circles, arcs ...