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Friday, 31 October 2014. Changing the subject of a formula. The formula for the area of a rectangle is: Area = Length X Width A = L X W A = LW. The letter a the front is called the SUBJECT of the formula. Area = Length X Width A = L X W A = LW. Area = 15 (cm 2 ).
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Friday, 31 October 2014 Changing the subject of a formula The formula for the area of a rectangle is: Area = Length X Width A = L X W A = LW The letter a the front is called the SUBJECT of the formula
Area = Length X Width A = L X W A = LW Area = 15 (cm2) What is the width? Length = 5 (cm) A = L X W 15 = 5 X W 15 = 5 X 3 So the width is 3 (cm)
Area = 15 (cm2) How did you do that? To find the width, I divided 15 by 5 15 ÷ 5 = 3 Length = 5 (cm) W = Area ÷ Length W = A ÷ L W = A/L A = L X W A = LW
Another formula can be found for the LENGTH Area = 15 (cm2) Width = 3 (cm) A = L X W A = LW Length = 5 (cm) W = Area ÷ Length W = A ÷ L W = A/L L = Area ÷ Width L = A ÷ W L = A/W
Here are the three formulae for a rectangle A is the subject A = L X W A = LW W is the subject L is the subject W = Area ÷ Length W = A ÷ L W = A/L L = Area ÷ Width L = A ÷ W L = A/W