1. Trial and Improvement 100 cm2 Example
In the rectangle below, the base is 2 cm more than the height. Find the height correct to 2 decimal places.
100 cm2

2. Example
In this triangle the length is 3 cm more than the width. Find correct to 1 decimal place the width.
15 cm2

3. Show that the volume of the box is given by the formula
Example
The net for an open box is made by cutting corners from a square card as shown.
Show that the volume of the box is given by the formula
Find the value of x which gives the maximum volume of the box.
10cm
x cm
x cm