AlgebraStudy Notes

Worked Example 3: Subject Appears Twice (Higher)

Part of Rearranging Formulae · GCSE GCSE Mathematics revision

This study notes covers Worked Example 3: Subject Appears Twice (Higher) within Rearranging Formulae for GCSE Mathematics. Revise Rearranging Formulae in Algebra for GCSE Mathematics with 14 exam-style questions and 11 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 5 of 6 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 5 of 6

Practice

14 questions

Recall

11 flashcards

Worked Example 3: Subject Appears Twice (Higher)

Make x the subject of: 3x + 5 = 2(x + y)

Step 1 Expand and collect x terms

3x + 5 = 2x + 2y

3x − 2x = 2y − 5

x = 2y − 5

Keep building this topic

Read this section alongside the surrounding pages in Rearranging Formulae. That gives you the full topic sequence instead of a single isolated revision point.

Worked Example 2: With a Square Knowledge Organiser: Rearranging Formulae Making a Letter the Star The Method: Reverse BIDMAS

Practice Questions for Rearranging Formulae

Make b the subject of the formula: a = b + c

A. b = a + c
B. b = c − a
C. b = a − c
D. b = ac

1 markfoundation

The circumference of a circle is given by the formula: C = 2πr Make r the subject of the formula.

2 marksfoundation

Quick Recall Flashcards

What is the 'subject' of a formula?

The variable that stands alone on one side of the equals sign. In v = u + at, v is the subject.

What does 'rearranging a formula' produce?

An equivalent formula expressing a different variable as the subject. E.g. v = u + at rearranges to a = (v − u)/t.

14 questions on Rearranging Formulae — practise free

Instant marking, adaptive difficulty, and 11 spaced repetition flashcards. Free until your GCSEs.

Try PrepWise Free

Worked Example 2: With a Square

Knowledge Organiser: Rearranging Formulae