Mathematics·Geometry·procedural
Understanding angles (age 12+)
Use ruler and compasses to perform standard constructions: perpendicular bisector of a line segment, perpendicular to a line from or at a given point, and bisecting an angle
Suggested ages 12–14
Evidence of understanding
- Construct the perpendicular bisector of a line segment using compasses and a straight edge
- Construct an angle bisector and verify by measuring both halves
- Construct a perpendicular from a point to a line using compasses only
Assessment prompt
If Understanding angles (age 12+) has only a ruler and a pair of compasses, can they construct a line that cuts another line segment exactly in half at a right angle — without using a protractor?
Standards alignment
7.G.2US · ccss-math
Draw geometric shapes with given conditions
Common Core State Standards for Mathematics · 7
KS3.Maths.Geo.4GB · uk-nc-2013
Standard Ruler and Compass Constructions
The national curriculum in England: Key stages 1 and 2 framework document · Key Stage 3