GCSE Secondary Maths Age 13-17 - Shapes & Area: Algebra - Explained

The video tutorial explains how to find the size of angle X in a diagram featuring a regular octagon and hexagon. It covers calculating the interior angles of these polygons and using the fact that angles around a point sum to 360 degrees to solve for X. The tutorial also discusses the marking scheme for the problem, emphasizing the importance of understanding interior angles of regular shapes.

What is the key characteristic of a regular polygon?

• All sides are of different lengths.

• All angles are equal.

• It is always a triangle.

• It has an odd number of sides.

How many degrees do the interior angles of a regular hexagon add up to?

• 1080 degrees

• 900 degrees

• 720 degrees

• 540 degrees

What is the measure of one interior angle in a regular hexagon?

• 120 degrees

• 100 degrees

• 140 degrees

• 90 degrees

What is the measure of one interior angle in a regular octagon?

• 150 degrees

• 140 degrees

• 135 degrees

• 145 degrees

If the angles around a point add up to 360 degrees, what is the value of angle X given the other two angles are 120 and 135 degrees?

• 95 degrees

• 105 degrees

• 100 degrees

• 110 degrees