The Unknown — What x Really Means | Class 10 · Algebra — Algebra Complete U1 | Namma Maths

I am thinking of a number. Triple it, add five, and you get twenty-six. What was my number? By the end of this lesson you will not guess it — you will prove it. This is Lesson 1 of Algebra Complete. A letter in maths is just a number wearing a coat — and today the coat comes off, honestly, one picture at a time. You will learn: • What x really is — a variable: a number that can travel • Expressions, terms, coefficients and constants (3x + 5 taken apart) • Substitution — the expression machine (3x + 5 at x = 4 gives 17) • Collecting like terms (7x + 3 − 2x + 5 = 5x + 8) • The distributive law — 2(x + 3) = 2x + 6, tested with real numbers, including the negative case −3(x − 2) = −3x + 6 • Equations as a balance: undo on BOTH sides, in reverse order, then check — 2x + 3 = 11, and the opening puzzle, solved and proved 📘 FREE NOTES for this lesson (printable PDF, with practice questions): https://drive.google.com/file/d/1a5Fe5sF2Q... CHAPTERS: 0:00 Hook — The Hidden Number 0:48 The Map — Eleven Lessons, One Method 1:02 The Letter — A Number in a Coat 2:08 Expressions — Terms, Coefficients, Constants 3:02 The Machine — Substitution 4:16 Like Terms — Collecting 5:32 Brackets — The Distributive Law 7:11 Equations — The Balance 9:51 Your Turn — Two Missions 10:32 Recap — Substitute, Undo, Check 11:07 Summary Card 11:18 Next Time — Both Sides of the Scale NEXT: U2 — Both Sides of the Scale: x on both pans, brackets inside. Algebra Complete playlist:    • Algebra Complete — Namma Maths   Music: "Frozen Star" by Kevin MacLeod (incompetech.com), licensed under CC BY 4.0.