1. Mensuration Objective Perimeter and area of shapes made from triangles and rectangles

2. Does anybody know what perimeter is? The perimeter of a shape is all the way around the shape. 3cm Perimeter =3+3+3+3 = 12cm Pick a starting point! Don’t forget units!

3. On your white boards find the perimeter of these shapes…

4. 8cm

5. 16cm

6. 12cm

7. 10m 4m 28m

8. 8m 10m 5m 2m 3m 8m 5m 51m

9. 4mm 10mm 5mm 6mm 42mm

10. Does anybody know what area is?Area is the amount of space inside a shape. Area of a rectangle length width Area of a rectangle = length x width Example Find the area of this rectangle 5cm 3cm Area = length x width Area = 5cm x 3cm Area = 15cm² Don’t forget the correct units!

11. On your white boards find the area of these rectangles…

12. 10cm 6cm 60cm²

13. 2mm 12mm 24mm²

14. 23km 2km 46km²

15. 2m 82cm 1.64m² or 16400cm²

16. Area of a triangle Length Height ---------------------------------------- ----------------------- Area = length x height _____________ 2 Example Find the area of this triangle 5cm 8cm Area = length x height _____________ 2 Area = 8cm x 5cm __________ 2 Area = 20cm²

17. On your white boards find the area of these triangles…

18. 10m 50m²

19. 6m 9m 27m²

20. 3km 5km Perpendicular height 7.5km²

21. 10mm 8mm 9mm 8mm 36mm²

22. Could you find the area of this shape? 10cm 12cm 5cm 6cm 30cm² 4cm 48cm² Area = 30cm² + 48cm² Area = 78cm²

23. 10m 14m 5m Could you find the area of this shape? 50m² 4m 5m 10m² Area = 50m² + 10m² Area = 60m²