Maths · KS3 Y7 · Algebra

Substituting into formulae

Substituting into formulaeFree6:44Heddy Score 3 of 7, below the standard

What you need to know

  • Letters in an equation are variables standing for numbers; y = 2x means y is always double x.
  • Some letters, such as π or G, are constants: fixed numbers written as letters.
  • Letters written next to each other are multiplied, and brackets are worked out before anything outside them.
  • To read a formula, first find out what every letter stands for, then decide which are variables and which are constants.

In this clip

0:14–4:00Reading algebraic notation
Also coversSubstituting into formulae
Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

1.7M views · 60.2K likes · Domain of Science 1.67M subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

Gives students a calm, general routine for reading any formula aloud and making sense of its letters.

Domain of Science on YouTubechecked 2026-10-22

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