Quadrilaterals: the family of four
Square, rectangle, rhombus, parallelogram, trapezium and kite: their sides, angles and diagonals, and why the angles always make 360°. Read one step, play with it, then tap “I understand this”.
Meet the family
A quadrilateral is any shape with 4 straight sides. We tell them apart by three things: sides (equal? parallel?), angles (right angles?) and diagonals (the lines from corner to corner).
The quadrilateral cards
Choose a quadrilateral and read its properties.
Sometimes two shapes look very much alike. A square and a rhombus both have four equal sides, but only the square’s diagonals are equal. The diagonals help you tell them apart.
Which shapes have …?
One property can fit several shapes. Think of each shape’s card from step 1.
Property hunt
Tap every shape the sentence is true for, then tap “Check”.
A square is also a rectangle
Quadrilaterals are like a family. A shape lower in the tree has all the properties of the shapes above it. The square at the very bottom is the most special: it is a rectangle, a rhombus, a parallelogram, a trapezium and a kite.
The family tree
Use the tree to answer yes or no.
“A square is a rectangle” is true, but “a rectangle is a square” is not always true. The arrow in the tree only works one way.
A rectangle is any quadrilateral with four right angles and equal opposite sides. A square follows all those rules, and has an extra one: all four sides are equal.
The angles add up to 360°
Draw a diagonal in any quadrilateral, and you get two triangles. Each triangle’s angles add up to 180°, so a quadrilateral’s four angles add up to 2 × 180° = 360°.
Find the missing angle
Choose the angle with the ?. Tap “Diagonal” to see the two triangles.
Correct: 0We already know that a triangle’s angles make 180°. A diagonal splits the quadrilateral into two triangles without losing any angle, so all the angles together are 180° + 180° = 360°.
Check yourself
- Parallelogram: 2 pairs of parallel sides. Trapezium: at least 1 pair.
- Rhombus: 4 equal sides. Rectangle: 4 right angles. Square: both.
- Kite: 2 pairs of adjacent sides equal; diagonals cross at 90°.
- The angles of a quadrilateral add up to 360° (two triangles).
Write these points in your maths book. Read them again the night before the test.
Quick questions
Tap an answer. If you get one wrong, read why and go back to that step. You get new questions every time.
You ticked all 4 steps! Now you are ready for the quiz.- Practice sheet for this classQuestions + memo · 1 A4 pagePractice sheet
- Space and shape10 pages · PDFPaperMemo
- Geometry8 pages · PDFPaperMemo
Ready for more? The Grade 7 quadrilaterals quiz gives you new questions every time.
- One step a day is enough. Ten calm minutes work better than an hour the night before the test.
- Look for quadrilaterals at home together: a door (rectangle), a tile (square), a kite in the park. Ask: “How do you know it is a rectangle and not a square?”
- Ask your child to tell you the rule in their own words. If they can explain it, they understand it.
- The ticks (“I understand this”) are saved on this device only. We never ask for names or emails.
Follows CAPS for Grade 7 Maths. Always check your teacher’s notes and textbook too.