Before the first unit, two quick things: a plain-language map of what Algebra I actually is, and a short, no-grade check to see which foundations are already solid — so we spend our time where it counts.
A plain-language tour of the same four ideas below — variables, expressions, graphing, and the rules — and how algebra grows straight out of the arithmetic you already know. Watch this before Unit 1.
▶ Watch the overviewAlgebra isn't one giant thing — it's four ideas that lean on each other. You've already met most of them since grade school.
A letter that holds the spot for a number we don't know yet — a box waiting to be filled.
□ + 3 = 7 becomes x + 3 = 7
Variables and numbers combined into a quantity — no equals sign, just something to build, simplify, or evaluate.
3x + 5
The picture of the algebra. Draw an equation and the pattern shows up at a glance — a line, a curve.
y = 2x + 1 → a line
The moves that keep things true: order of operations, distributing, doing the same thing to both sides.
2(x + 3) = 2x + 6
No grade. No time limit. Nothing to study for.
Answer what you can, skip what you don't know (guessing hides the gap). At the end you'll get a map: what's solid, and for anything shaky, a direct link to the lesson that fixes it.
Una versión en español está en camino.