Know and use the sum of the angles at a point is 360°.
Know and use the sum of the angles at a point is 360°.
Know that the sum of the angles at a point on a line is 180°.
Know and use:
vertically opposite angles are equal
alternate angles on parallel lines are equal
corresponding angles on parallel lines are equal.
Derive and use the sum of the interior angles of a triangle is 180°.
Derive and use the sum of the exterior angles of a polygon is 360°.
Find the sum of the interior angles of a polygon.
Find the interior angle of a regular polygon.
Apply these angle facts to find angles in rectilinear figures, and to justify results in simple proofs.
e.g. The sum of the interior angles of a triangle is 180°.
Apply these angle properties in more formal proofs of geometrical results.