# Geogebra 1 - Basics

## Understanding centroid and circumcentre

Requirement 1. Draw two different triangles (let's say Triangle A and Triangle B) without intersecting each other. 2. Construct centroid on Triangle A and construct circumcentre on Triangle B. 3. Draw a circle with circumcentre as center and encloses the Triangle B. 4. Besides, You should also name the centroid and circumcentre with different color. 5. Add your name, class and class number on your work and submit the graph. Marking Total 10 (+2) Marks 1. Correct triangles : (1 M) 2. Centroid (lines through mid-point and vertex : 2 M, intersection : 1 M) 3. Circumcentre (perpendicular bisectors : 2 M, intersection and draw circumcircle : 1 M) 4. Circle encloses triangle (2 M) 5. Format : (1 M) 6. Bonus : (2 M) Reference: Definiton of Centroid: http://en.wikipedia.org/wiki/Centroid Definition of Circumcentre: http://en.wikipedia.org/wiki/Circumcentre Geogebra Tutorial 1 - Basis https://www.youtube.com/watch?v=1cBXWi66-tY Geogebra Tutorial 2 - Insert Text https://www.youtube.com/watch?v=xLYvdgJ6fyg Yahoo 知識: http://hk.knowledge.yahoo.com/question/question?qid=7009052302073