Changing the Subject of a Formula (Leaving Cert Mathematics): Flashcards
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Practise the cards
12 cards from this deck
Subject of a formula
Subject of a formula
Variable on left-hand side, expressed in terms of others
Changing the subject of a formula
Changing the subject of a formula
Rearranging so different variable appears alone on left
Key principle for changing formula subject
Key principle for changing formula subject
Same operation on both sides keeps equation unchanged
Operations allowed on both sides of equation
Operations allowed on both sides of equation
Add, subtract, multiply, or divide
First step to change formula subject
First step to change formula subject
Identify the variable you want to make the subject
Order for undoing operations on variable
Order for undoing operations on variable
Work in reverse order - undo last operation first
Unwrapping analogy: which layers to remove first?
Unwrapping analogy: which layers to remove first?
Outer layers first (work in reverse order)
Technique for fractions when changing subject
Technique for fractions when changing subject
Clear fractions early by multiplying through by denominators
When to factor out the target variable
When to factor out the target variable
When it appears in multiple terms
How to check your rearranged formula
How to check your rearranged formula
Substitute answer back into original equation
Common mistake when moving terms across = sign
Common mistake when moving terms across = sign
Forgetting to change the sign
Final step in changing formula subject method
Final step in changing formula subject method
Check your final answer makes sense