establish the formula for the area of a rectangle and use it to solve practical problems
Elaborations
using the relationship between the length and area of square units and the array structure to derive a formula for calculating the area of a rectangle from the lengths of its sides
using one-centimetre grid paper to construct a variety of rectangles, recording the side lengths and the related areas of the rectangles in a table to establish the formula for the area of a rectangle by recognising the relationship between the length of the sides and its calculated area
solving problems involving the comparison of lengths and areas using appropriate units
investigating the connection between the perimeters of different rectangles with the same area and between the areas of rectangles with the same perimeter
