Middle School Grade 9 mathematics
Middle School Grade 9 covers square roots and real numbers, trig ratios, circle properties, and statistical dispersion. All 5 activities for this grade are translated into English, with the same quizzes and best-score tracking as the Korean site.
🔢 Number & operations
📐 Shape & measurement
📐
Trig Ratios (Sine, Cosine, Tangent) Lab
Choose an angle and which side to fix, and watch how sin, cos, and tan change.
Open English lesson → ⚪Inscribed Angle Lab
Move a point around a circle and see why the inscribed angle always stays exactly half the central angle.
Open English lesson → 🔵Circle Properties Lab
Explore how a circle relates to a line, sector arcs and areas, tangent lines, and inscribed polygons.
Open English lesson →📊 Data