Author note — to cover

Rearrange formulae by inverse operations where the subject appears once and unpowered, e.g. v = u + at for t, y = mx + c for x, including subjects inside a bracket or multiplied by a fraction. Squares, roots and twice-appearing subjects are the sibling pages, the latter Higher. Both tiers. (A5)

• Fluency — direct questions on changing the subject of a formula, limited to this lesson's stated scope (4 questions).
• Application — use the same skill in unfamiliar or contextual questions without introducing a later method (4 questions).
• Check — questions built around the exclusions and likely misconceptions named in the lesson brief (4 questions).