Area using formulas for square and rectangle
For some shapes it may be easier to calculate their area using an appropriate An equation that is written for a purpose, such as converting Fahrenheit to Celsius. A formula is always true regardless of the values used..
Area of a square = length2
This means length × length.
Given the area, we can find the length of a square by calculating the The square root of a number is a number which, when multiplied by itself, gives the original number. So the square root of 25 is 5 (5 × 5 = 25).. The symbol for square root is \(\sqrt{}\)
Question
The area of a square is 36 m2. How long is each side?
6 m.
To work this out, use the square root button on your calculator. You could also solve it by asking ‘what number multiplied by itself gives 36?’
Area of a rectangle = length × width
Given the area, we can divide by the length to calculate the width.
Question
A rectangular room has length 5 m and width 6 m. One carpet square measuring 1 m by 1 m costs £15. How much would it cost to carpet the room?
Area = length × width
Area = 5 × 6 = 30 m2
Each square costs £15
30 × £15 = £450
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