Area and the box method

• Wiskunde
• Middelbare school
• havo, vwo
• Leerjaar 1

Welcome to maths

Need: 

• Book open on p. 123 (you can start with 37 and 38)
• Notebook open on an empty page (with a margin)
• Pen 
• Pencil (+sharpener and eraser)
• Geo triangle

2mm + 0.2dm + 3hm = .....m.
Question by a student :-) 

 Did you check your homework?

Yes? Start with ex. 37 and 38 on p. 115

No? first check and correct your homework

base = basis

height = hoogte

opposite = ertegenover liggend

Do you remember the words

line segment, perpendicular, vertex, arms, obtuse/acute?

Goal

• Know what an area is and how to calculate an area 
• Write down calculations in a short and formal way
• Check your work 

Which formula do you use for
calculating the area of a triangle?

Calculate the area of this triangle and share your workings.

Calculate the area of triangle ABC (copy figure in notebook).

- Calculate the area of the rectangle.
- Calculate the areas of triangle I, II and III
- Area rectangle - area of the triangles = area triangle ABC

Calculate the area of triangle PQR and add a picture.


- Done? Continue with 37, 38 and 39 on p. 123

Convert.
a. 750 dm^2 = ..... mm^2
b. 20 000 dam^2 = ...... km^2
Extra:
c. 8 100 mm^2 = ..........dam^2

Answer like this : 

75 / 12 / 81

Work on...

• exercises 37, 38, 39 (and 40) on p. 123
• Check your work after 8 minutes with a different colour
• Copy HW in your planner
• HW Thursday: Do ex. 37, 38 and 39 p. 123

Next lesson

• You have finished and checked your homework 
• HW Thursday: Do ex. 37, 38 and 39 p. 123
• We will work on the properties of a circle