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EXAMPLE:3             An angle LAOB is given. Draw a ray ox, bisecting LAOB.                                               TO DRAW A LINE PAR ALLEL TO A GIVEN LINE THROUGH A POINT OUTSIDE IT
                              Steps of construction
                              Let  AOB be given.                                                                                   EXAMPLE: 6           A line XY is given and Pis a point outside it. Draw a line through P parallel to XY.
                              1. With O as centre and any convenient radius, draw an arc.                                                               Steps of construction
                                  cutting OA and OB at P and Q respectively.                                                                            Let XY be the given line and P be a given point outside it.          R  P
                              2. With centre P and radius more than - (PQ), draw an arc.                                                                1.Take any point Q on XY.
                              3. With centre Q and the same radius as before, draw another                                                              2.Join QP.
                                arc, cutting the previously drawn arc at a point R.                                                                     3.Draw  RPQ such that   RPQ =   PQY
                              4. Join OR and produce it to any point X.                                                                                    as shown in the figure.                                 X     Q            Y
                              Then, ray OX bisects   AOB.                                                                                               4.Extend RP on both sides.
        Verification          Measure  AOX and   BOX.                                                                                                      Then, the line RP passes through the point P and RP || XY.
                              You would find that   AOX =   BOX.


        TO DRAW A LINE PERPENDICULAR TO A GIVEN LINE FROM A POINT ON IT
        EXAMPLE:4 A line XY is given and Pis a point on it. Draw a line through P perpendicular to XY.
                       Steps of construction
                       Let XY be the given line and P be a point on it.
               1.      With centre P and any radius, draw a semicircle to intersect XY at A and B.
               2.      With centre A and any radius more than PA, draw an arc.
               3.      With centre B and the same radius, draw another arc,
                       cutting the previously drawn arc at Q.
               4.      JoinPQ.
                       Then, QP 1- XY.
        Verification   Measure   QPX and   QPY.
                       You would find that   QPX =   QPY = 90°.

        TO DRAW A LINE PERPENDICULAR TO A GIVEN LINE FROM A POINT OUTSIDE IT
        EXAMPLE:5             A line XY is given and P ts a point outside it. Draw a line through P perpendicular
                              to XY.
                              Steps of construction
                              Let XY be the given line and P be a point outside it.
                              1. With P as centre and a convenient radius, draw an arc
                                   intersecting XY at A and B.
                              2.With A as centre and a radius greater than - (AB), draw
                               an arc.
                              3.With Bas centre and the same radius, draw another arc,
                                 cutting the previously drawn     arc at Q.
                              4.Join PQ, meetingXY at L.
                                 Then, PL is the required perpendicular on XY.

                              Verification Measure LPLX and LPLY.
                              You would find that LPLX = LPLY = 90° .
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