Angles Special Quadrilaterals Demonstration This resource provides animated

Angles – Special Quadrilaterals – Demonstration This resource provides animated demonstrations of the mathematical method. Check animations and delete slides not needed for your class.

Can you name these types of quadrilateral? Rectangle Parallelogram Trapezium Rhombus Kite

Can you identify pairs of parallel sides? Rectangle Parallelogram Trapezium Rhombus Kite

Look at the interior angles of the quadrilaterals. Can you spot pairs of equal angles? Rectangle Parallelogram Trapezium Rhombus Kite

In a rectangle, this pair of parallel sides create two 90° angles. What happens to the 2 angles if we slant the line?

bigger smaller

Can you spot pairs of angles on the intersecting line? Total = 180° Because angles on a straight line total 180° in total The parallel lines meet the intersecting line at the same angle. So the interior angles will total 180°.

When a line intersects a pair of parallel lines, the interior angles total 180°.

When a line intersects a pair of parallel lines, the interior angles total 180°. =180° Trapezium What type of quadrilateral is this? Where are the pairs of angles that total 180°?

When a line intersects a pair of parallel lines, the interior angles total 180°. =180° Isosceles Trapezium What type of quadrilateral is this? Where are the pairs of angles that total 180°?

When a line intersects a pair of parallel lines, the interior angles total 180°. Each pair of adjacent angles total 180°. What type of quadrilateral is this? Where are the pairs of angles that total 180°? Parallelogram

When a line intersects a pair of parallel lines, the interior angles total 180°. Trapezium What type of quadrilateral is this? Where are the pairs of angles that total 180°?

When a line intersects a pair of parallel lines, the interior angles total 180°. What type of quadrilateral is this? Where are the pairs of angles that total 180°? Rhombus

same larger These opposite angles have increased by the same amount. A smaller If we move point A down, what type of quadrilateral do we create? What happens to each angle? a kite

In a kite, the pairs of adjacent equal sides create symmetry. The symmetry means the kite always has one pair of equal opposite angles.

Because kites are symmetrical, the diagonals are always perpendicular : they cross at 90°.

Rectangle Parallelogram with equal angles Special Quadrilaterals • • Parallelogram Parallel opposite sides Equal opposite angles Diagonals bisect each other Rhombus Parallelogram with equal sides • Diagonals bisect each other at 90° • Diagonals bisect the angles Isosceles Trapezium • 2 Parallel sides • A + B = 180° A A A B B B Square Parallelogram with equal sides & equal angles A B Kite • 2 Pairs of equal adjacent sides • A=B • Longer diagonal bisects shorter at 90°

Find the missing angles (A to D) & name all the quadrilaterals. A Trapezium A Parallelogram A 65° Trapezium A Rhombus E F B = 115° D = 116° G D E = 124° 64° 42° 309° F = 56° 114° I H L = 82° Trapezium 35° I = 97° C = 61° G = 138° 56° Trapezium 119° B A = 60° 120° C H = 114° A Kite 67° 130° J J = 113° L K K = 51° A Kite 66°

Questions? Comments? Suggestions? …or have you found a mistake!? Any feedback would be appreciated . Please feel free to email: tom@goteachmaths. co. uk