1. Rearranging Equations
How To Change the Subject of Equations

2. Equation to find area of the rectangle below: A = B x H
This equation can also be written as:
32÷ 8 = 4
32÷ 4 = 8
What is the “subject” in each equation?

3. If the Area is 98 𝑐𝑚 2 , the Base is 14cm and the height of the square is not given…
Equation: A = B x H
One equation is:
98 = 14 x H
Can you rearrange and write more equations?
Can you work out the height?
AREA = 98

4. How to rearrange complex equations?
METHOD 1
Isolate the pronumeral by reversing the operations;
whatever changes you do on one side of the equal sign should be done on the other side as well.
METHOD 2
Backtrack Flow Chart

5. The opposite of the operations

6. Example Solution: 𝑑+5= 20 (subtract 5 from both sides) 𝑑+5 −5=20−5
Make 𝑑 the subject of the formula in the equation: 𝑑+5=20
Solution:
𝑑+5= 20 (subtract 5 from both sides)
𝑑+5 −5=20−5
𝒅=𝟐𝟎−𝟓

7. METHOD 2 Backtrack Flow Chart
Make 𝑑 the subject of the formula in the equation: 𝑑+5=20
Solution
Start with the variable “d”