Why Does the Sign Flip? | Inequalities

A tipped scale doesn't have ONE answer… it has infinitely many. In this video you'll solve one-variable inequalities, graph the solution on a number line and, above all, SEE why the inequality sign flips when you multiply or divide by a negative number — with a mirror. In this video you'll learn: ✔ The inequality symbols (less than, greater than, ≤, ≥) and how to read them ✔ Graphing the solution on a number line: open vs closed circle ✔ Solving an inequality just like an equation ✔ The mirror: why "2 is less than 5" becomes "−2 is greater than −5" ✔ 3 examples from easy to exam level, the "forgot to flip" trap + a 5-second challenge ✔ Real life: minimum grade average, speed limits and elevator capacity ⏱️ CHAPTERS 0:00 The tipped scale 0:34 The inequality symbols 1:05 Graphing the solution: open or closed circle 1:34 Solve it like an equation 2:03 Why does the sign flip? The mirror 2:43 Dividing by a negative 3:10 Example ladder 4:17 The trap: forgetting to flip the sign 4:51 5-second challenge 5:36 Real world: grades, speed limits, elevators 6:21 3-card recap 6:42 Wow fact: Harriot and the Moon ◀️ Previous: AL-05 · Equations with Fractions ▶️ Next: AL-07 · Special Products 📚 Full playlist: The X Lab · Algebra 1 💬 Tell me in the comments: what's the solution to −5x ≤ 20? 👍 If this helped, hit like and subscribe — new visual math every week. 🇪🇸 ¿Prefieres en español? → @AlgebrayTrigonometria #math #algebra #inequalities #algebra1 #mathhelp #SATmath #mathtricks