Geometric Constructions ... Animated!
"Construction" in Geometry means to draw shapes, angles or lines accurately.
These constructions use only compass, straightedge (i.e. ruler) and a pencil.
This is the "pure" form of geometric construction - no numbers involved!
|Learn these two first, they are used a lot:|
|And it is useful to know how to do 30°, 45° and 60° angles. You can use the angle bisector method (above) to create other angles, such as 15°, etc:|
|30 Degree Angle|
|45 Degree Angle|
|60 Degree Angle|
|Points and Lines:|
|Perpendicular to a Point on a Line|
|Perpendicular to a Point NOT on a Line|
|Parallel Line through a Point|
|Same (Congruent) Angle|
|Cut a line into N segments|
|Center of a Circle|
|Point to Tangents on a Circle|
|Inscribe a Circle in a Triangle|
|Circumscribe a Circle on a Triangle|
|Circle touching 3 Points|
|And for the "Master Class", a Pentagon|