This video is a comprehensive, start-to-finish review of every circle concept tested on the Digital SAT, organized by frequency and importance. It walks students through how to recognize each circle question type, which formulas matter, and where students are most likely to make mistakes.

The lesson begins with area and circumference, emphasizing that formulas are given on the equation sheet and that most traps involve radius vs. diameter. You see both simple plug-and-chug questions and multi-step comparison problems where students must track relationships across multiple circles.

Next, the video covers arcs and sectors, clearly defining vocabulary (arc vs. sector, central angle, minor vs. major arc) and showing how these problems reduce to fractions of the circle using

• Arc = circumference × θ / 360

• Sector = area × θ / 360

You then move into radians vs. degrees, learning how to convert using

• 180° = π radians
  and treating conversions like unit-conversion problems, plus when to use degree-based vs. radian-based formulas.

The final section focuses on tangent lines and angles, narrowing the topic to only the rules the SAT actually tests:

• Inscribed angles are half of central angles (or intercepted arcs)

• Angles inscribed in a semicircle are always 90°

• A radius drawn to a tangent line is perpendicular

Each topic includes both easy and harder SAT-style examples, showing that difficulty usually comes from extra information and diagram interpretation, not new math. Big takeaway: circle questions on the SAT reward diagram literacy, keyword recognition, and structured setup—not memorization.