Page 194 - ICSE Math 8
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3.  Taking E as centre and radius = 5 cm, draw an arc on EX intersecting   X
                                    it at point A.                                                        A
                                  4.  At point A on line EA, make –EAY = 90º using a
                                    protractor.                                                4.5 cm   90º
                                  5.  Taking A as centre and radius = 4.5 cm, draw an arc   R                   5 cm
                                    on AY intersecting it at point R. Joint RD.      Y
                                    Hence, DEAR is the required quadrilateral.
                                                                                                                60º
                                                                                                     D       4 cm      E


                                                             EXERCISE 17.4

                      1.  Construct a quadrilateral FUSE in which FU = 5.2 cm, US = 4.6 cm, SE = 5.8 cm, ∠U = 30º and
                        ∠S = 150º.
                      2.  Construct a quadrilateral PINE in which PI = 3.5 cm, IN = 5.5 cm, NE = 5 cm, ∠I = 125º and ∠N = 80º.
                      3.  Construct a quadrilateral PACE in which PA = 5.4 cm, AC = 5.7 cm, PE = 4.5 cm, ∠P = 120º and
                        ∠A = 115º. What is the measure of the side CE?
                      4.  Construct a quadrilateral MUST in which MU = 8 cm, US = 4 cm, ST = 6 cm, ∠U = 40º and ∠S = 85º.
                      5.  Construct  a  quadrilateral DART  in  which  AR  =  5.6 cm, RT  =  3.4 cm, DT =  4.6  cm,  ∠R  = 90º and
                        ∠T = 105º.


                    Construction of a Quadrilateral Given 3 Angles and 2 Included Sides             S
                    Example 5:    Construct a quadrilateral  MARS in which  MA = 5.2 cm,
                                  AR = 3.8 cm, –M = 100º, –A = 65º and –R = 130º.                               130º  R
                    Solution:     Construction: Draw a rough sketch of the figure to be                               3.8 cm
                                  constructed.                                                           100º     65º
                                                                                                            5.2 cm
                                  Steps of Construction:                                              M  Rough sketch  A

                                  1.  Draw a line MA = 5.2 cm.                              X
                                  2.   At point M on line MA, draw –AMX = 100º. Also at point   S             Y
                                     A on line MA, draw –MAY = 65º using a protractor.                          R

                                  3.    Taking A as centre and radius = 3.8 cm, draw an arc on
                                     line AY intersecting it at point R.                                    130º

                                  4.   At point R on line AR, draw –ARS = 130º using a protractor                  3.8 cm
                                    intersecting line MX at S. Join RS.
                                                                                                   100º           65º
                                      Hence, MARS is the required quadrilateral.                 M       5.2 cm        A


                                                             EXERCISE 17.5

                      1.  Construct a quadrilateral MIKE in which MI = 5 cm, IK = 4 cm, ∠M = 80º, ∠I = 85° and ∠K = 125º.
                      2.  Construct a quadrilateral WEST in which WE = 5 cm, ES = 3.2 cm, ∠W = 55º, ∠E = 100º and ∠T = 90º.
                      3.  Construct a quadrilateral BUNK in which BU = 4 cm, UN = 7 cm, ∠B = 110º, ∠N = 110º and ∠K = 80º.
                      4.  Construct  a quadrilateral  TURN in which  UR = 4.7 cm,  RN = 5.8 cm,  ∠T = 60º,  ∠U = 100º and
                        ∠R = 70º.


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