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Updated Mar 22, 2026

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2 pages

Mastering Changing the Subject Formula: Practice Questions & Answers

kai

@kai55

Learning to rearrange formulas is like solving puzzles with letters... Show more

# Changing the Subject Formula Questions

1. k=2f+5
Make f the subject of the formula.

2. k= 5h-3
Make h the subject of the formula.

Make

Formula Rearrangement Practice Problems

These formula rearrangement questions will test your ability to isolate different variables. You'll work with linear equations, expressions with brackets, and even square roots.

The problems start simple with basic addition and subtraction, then progress to more challenging scenarios. Some involve expanding brackets first, whilst others require you to work backwards from square root expressions.

Each question asks you to make a specific variable the subject of the formula - this means getting that letter on its own on one side of the equals sign. Remember, whatever operation you do to one side, you must do to the other side too.

Top Tip: Always work systematically through each step and write down every stage of your working - this helps you spot mistakes and shows your method clearly.

Step-by-Step Solutions

The worked solutions demonstrate the systematic approach needed for successful formula manipulation. Each answer shows every step of the rearrangement process clearly.

For simple linear equations like k = 2f + 5, you simply use inverse operations in reverse order. Subtract 5 from both sides, then divide by 2 to isolate f. The key is doing the opposite of what's happening to your target variable.

When brackets appear, like in s = 3 $a + 5b$ , you must expand the brackets first before rearranging. This gives you s = 3a + 15b, then you can subtract 3a and divide by 15 to find b.

Remember: The order matters! Always follow BIDMAS in reverse - deal with addition/subtraction before multiplication/division when rearranging.

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Updated Mar 22, 2026

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2 pages

Mastering Changing the Subject Formula: Practice Questions & Answers

kai

@kai55

Learning to rearrange formulas is like solving puzzles with letters instead of just numbers. You'll master the essential skill of making any variable the subject of a formula by using inverse operations systematically.

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Formula Rearrangement Practice Problems

These formula rearrangement questions will test your ability to isolate different variables. You'll work with linear equations, expressions with brackets, and even square roots.

Top Tip: Always work systematically through each step and write down every stage of your working - this helps you spot mistakes and shows your method clearly.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

Step-by-Step Solutions

The worked solutions demonstrate the systematic approach needed for successful formula manipulation. Each answer shows every step of the rearrangement process clearly.

When brackets appear, like in s = 3 $a + 5b$ , you must expand the brackets first before rearranging. This gives you s = 3a + 15b, then you can subtract 3a and divide by 15 to find b.

Remember: The order matters! Always follow BIDMAS in reverse - deal with addition/subtraction before multiplication/division when rearranging.