Topic explanation

Standard explanation

From a point on the circle, exactly one tangent. The radius is the perp from O to the tangent, so it is the shortest path from O to the line.

Key points

• one point of contact
• touches at one point
• radius perp tangent
• keep the ideas separate
• Definition And 90 Deg: From a point on the circle, exactly one tangent. The radius is the perp from O to the tangent, so it
• WHAT — DEFINITION AND 90 DEG: From a point on the circle, exactly one tangent. The radius is the perp from O to the tangent, so it
• HOW — Use the idea: Identify what is given, select this topic's rule or evidence, apply it one step at a time, and check
• CORE UNDERSTANDING: From a point on the circle, exactly one tangent. The radius is the perp from O to the tangent, so it

Labelled diagram