2Menu Construction 1a Construct a triangle (ASA) Construction 1b Construct a triangle (SAS)Construction Construct the bisector of an angleConstruction Construct the perpendicular bisectorof a line segment.Construction Construct the circumcircle of a triangle.Construction Construct the incircle of a triangle.Construction Divide the line segment [ab] into threeequal parts.
3Construct the triangle PQR where |QR|=8cm, | PQR|=52o and |PRQ|=46o (A S A) Draw a line segment [QR] 8cm in length. Name the points and mark the length.At Q using a protractor mark and draw an angle of 52o.At R mark and draw an angle of 46oMark the point of intersection of the two angles.This is the point P.P52°46°QuitQ|QR|=8cmRMenuEND OF CONSTRUCTION
4Construct a triangle ABC where |AB| = 12cm, | BAC|=65o and |AC| = 9 cm (S A S) USE MOUSE CLICKS TO VIEW CONSTRUCTIONDraw a line segment 12cm in length. Name the points and mark the length.Use a protractor to draw a line at 65o to |AB|.Use a compass with A as centre and 9cm radius to draw an arc on this line.Mark the point of intersection C.Join C to B and complete labels.C|AC|=9cm65°QuitAb|AB|=12cmMenuEND OF CONSTRUCTION
5Construct the bisector of an angle Draw the angle AOB.Using the vertex o as centre draw an arc to meet the arms of the angle at X and Y.Using X as centre and the same radius draw a new arc.Using Y as centre and the same radius draw an overlapping arc.Mark the point where the arcs meet.The bisector is the line from O to this point.AXXXOQuitYMenuBEND OF CONSTRUCTION
6Construct the perpendicular bisector of a line segment Draw the line segmentUsing A as centre and a radius greater than half |AB| draw an arc.Using B as centre and the same radius draw another arc.Draw a line through the points where the arcs cross.ABQuitMenuEND OF CONSTRUCTION
7Construct the circumcircle of a triangle BDraw the triangle ABCConstruct the perpendicular bisector of [AB]Construct the perpendicular bisector of [AC]QuitThe bisectors meet at O the circumcentre of the triangleUsing O as centre and |OA| as radius construct the circumcircle of the triangle ABCMenuEND OF CONSTRUCTION
8Construct the incircle of a triangle XOXBCDraw the triangle ABCConstruct the bisector of angle ABC as shown.Construct the bisector of angle ACB as shown.The bisectors meet at point O, the incentre of the triangleUsing O as centre construct the incircle of the triangle ABCQuitMenuEND OF CONSTRUCTION
9Divide the line segment [AB] into three equal parts Draw the line segment [AB].Through A draw a line at an acute angle to [AB].On this line use circle arcs of the same radius to mark off three segments of equal length [AR], [RS] and [ST].Join T to B.Through S and R draw line segments parallel to [TB] to meet [AB] at D and C.Now |AC|=|CD|=|DB|ACDBRSQuitTMenuEND OF CONSTRUCTION