Prove that $CD$ is a diameter of the circle.

Which of the broken lines in the given figure are lines of symmetry?

Find the unknown angle $x$. 

Which of the following figures have both line and rotational symmetry?

Draw the lines of symmetry on this shape.

$A, B$ and $C$ are points on the circumference of a circle centre $O$.

$OAD$ is a straight line and angle $DAB=142°$.

Calculate the size of angle of $ACB$.

$A, B, C$ and $D$ lie on the circumference of the circle.

Find the value of $t$.

$X, Y$ and $Z$ lie on the circumference of the circle, centre $O$.

Find the value of $w$, giving reasons for your answer.

$E, F, G$ and $H$ lie on the circumference of the circle.

Find the value of $p$, giving a reason for your answer.