Loci
A locus is a set of points satisfying a specific condition, and understanding common loci helps solve geometric construction problems.
Core concept
The locus of points equidistant from a fixed point is a circle, with the fixed point as centre and the distance as radius.
How it works
The locus of points equidistant from two fixed points is the perpendicular bisector of the line segment joining those points.
Why it matters
The locus of points equidistant from two intersecting lines is the angle bisector of the angles formed by those lines.
Key detail
Understanding loci helps solve construction problems and describe geometric relationships between points and given conditions.
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Quick notes
• Locus is a set of points satisfying a condition.
• Equidistant from a point: locus is a circle.
• Equidistant from two points: locus is the perpendicular bisector.
• Equidistant from two lines: locus is the angle bisector.
• These are common locus types.
• Loci help solve construction problems.
• They describe geometric relationships.
• Practice builds locus identification skills.