The surface area of a pyramid whose base is a regular polygon.

This is a centred pyramid that has a regular polygon as a base.

The area of a regular polygon is calculated by multiplying its perimeter by its apothem and dividing it by 2.

Its lateral faces are all equal. The slant height of the piramid is the height of the triangle of a lateral face.
The lateral area of this pyramid is calculated by multiplying the perimeter of the base by the slant height and dividing it by 2.

To find the total surface area of a pyramid we add up the surface area of its base and the lateral surface area.

You can rotate the figure by moving the red dot. What you are going to measure has to be straight.

Move the ruler from its ends, one after the other.

Do measurements in centimetres, if the value is not a whole number, use a decimal number. To separate the whole part from the decimal part, you have to use a dot instead of a comma.

Write down each measurement in the box below and hit Enter. If it is correct, it will appear in the window.

Do the necessary calculations to find the perimeter of the base, the surface area of the base and the lateral surface area. Write it down in the corresponding boxes below.

Take  the corresponding units to each yellow circle.