The angle at the centre of a circle is twice the angle on the circle subtended by the same arc.
The angle at the centre of a circle is twice the angle on the circle subtended by the same arc.
On the left, the angle at the centre of a circle is twice the angle on the circle subtended by the same arc.
on the right, shows by comparing the arc is different for the less than 180 angle, a common misconception among students.
the visualisation allows a direct comparison of the correct concept with the common error.