Trapezium

Today, we are going to learn about trapeziums, which are quadrilaterals with at least one pair of parallel sides. Can anyone tell me what a quadrilateral is?

A quadrilateral is a shape with four sides.

That's right! Now, can someone explain why a trapezium must have at least one pair of parallel sides?

Because that's what makes it a trapezium, unlike other quadrilaterals!

Excellent point! For memory, we can use the acronym 'TAPP'—Trapezium Always has Parallel sides. Now, let's look at some figures to identify which are trapeziums.

Can we draw our own examples?

Absolutely! Let's create our own trapeziums on the board and mark the parallel sides.

Great work with the trapeziums! Now, let's talk about a special type called an isosceles trapezium, where the non-parallel sides are equal. How can we identify an isosceles trapezium?

The non-parallel sides should be the same length!

Exactly! Remember, 'Isosceles' features 'Equal sides.' Let’s draw one together.

Is a square a type of trapezium?

That's a great question! A square has all sides equal and fits the criteria of a trapezium because it has two pairs of parallel sides. Let's create a list comparing different trapezium types on the board.

For our next activity, we'll use triangle cut-outs to form trapeziums. Who remembers which pairs we can use to build an isosceles trapezium?

We can use two triangles of the same size!

Correct! Now let's start arranging our triangles. After that, we will use set-squares to see how many different trapeziums we can create.

Do we need to measure the sides?

Yes! Measuring the non-parallel sides helps us to confirm if it's an isosceles trapezium. Let’s record our findings on the class board.