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17.2 Rotating shapes



               )     Exercise 17.2

               1  Copy each diagram and rotate the shape about the centre C by the given number of degrees.
                  a                      b                       c                      d

                          C     C    C     C                 C     C    C     C  C     C    C     C
                                         C     C    C     C


                          180°  180°  180°  180° 90 °   90° anticlockwiseanticlockwise  90 °   90° clockwise 180°  180°  180°
                                                                               180°
                                                                  °
                                                           °
                                                          90° clockwiseclockwiseclockwise
                                                         90
                                        90° anticlockwiseanticlockwise
                                                                90
               2  Copy each diagram and rotate the shape about the centre C by the given fraction of a turn.
                  a                      b                       c                      d
                            C     C    C      C                C     C     C   C C   C    C     C
                                           C     C     C     C

                         1 / 2 turn  1 / 2 turn / 2 turn  1 / 2  turn  1 / 4  1 / 4  1 / 2 turn  1 / 2 turn / 2 turn  1 / 2 1  turn  1 / 4  1 / 4
                                    1
                                                                        1
                                                                         1
                                        1
                                             1
                                                                          / 4 turn anticlockwise turn anticlockwise turn anticlockwise turn anticlockwise
                                        / 4 turn clockwise turn clockwise turn clockwise turn clockwise
                                                                                / 4
                                              / 4
               3  Copy each diagram and rotate the shape, using the given information.
                  a    y  y   y  y       b  y  y  y  y         y   c  y  y  y       y    d  y  y
                                                                                       y
                       6  6  6   6         6  6  6   6         6  6   6  6         6   6  6  6
                       5  5  5   5         5  5  5   5         5  5   5  5         5   5  5  5
                       4  4  4   4         4  4  4   4         4  4   4  4         4   4  4  4
                       3  3  3   3         3  3  3   3         3  3   3  3         3   3  3  3
                       2  2  2   2         2  2  2   2         2  2   2  2         2   2  2  2
                       1  1  1   1         1  1  1   1         1  1   1  1         1   1  1  1
                       0  0  0   0         0  0  0   0         0  0   0  0         0   0  0  0
                                               x
                                                                   x
                                                                                       x
                                                                                                  x 5 6 4 3
                                                         x 5 6 4 3
                        0  1 2 0  3 1 2 0  4 3 1 2 0 5 6 4 3 1 2  x 5 6 4  x 0 5 6 1 2 0  3 1 2 0  4 3 1 2 0 5 6 4 3 1 2  x 5 6 4  x 0 5 6 1 2 0  3 1 2 0  4 3 1 2 0 5 6 4 3 1 2  x 5 6 4  x 0 5 6 1 2 0  3 1 2 0  4 3 1 2 0 5 6 4 3 1 2  x 5 6 4  x 5 6  x
                                                                             x 5 6 4 3
                                     x 5 6 4 3
                        90° anticlockwise          180°                 90° clockwise             180°
                          centre (1, 3)          centre (3, 3)          centre (1, 1)           centre (4, 3)
               4  The diagram shows seven triangles.    y
                                                        8                         To describe a rotation you need to:
                 Describe the rotation that takes:      7   A
                                                                B
                                                        6                         1   give the number of degrees or
                  a  triangle A to triangle B           5               E
                                                                  C                  fraction of a turn
                  b  triangle B to triangle C           4
                                                        3       D
                  c  triangle C to triangle D           2                         2   if the turn is not 180°, say
                  d  triangle C to triangle E           1     G     F                whether the turn is clockwise
                                                        0
                  e  triangle F to triangle G.           0  1 2  3  4  5 6  7  8  x  or anticlockwise
                                                                                  3   give the coordinates of the
               5  a  Copy this diagram.
                   Follow these instructions to make a pattern.                      centre of rotation.
                   i       Rotate the pattern a quarter-turn clockwise about the
                         centre C.
                    ii  Draw the image.
                    iii  Rotate this new image a quarter-turn clockwise about the centre C.
                    iv  Draw the image.
                   v  Rotate the third image a quarter-turn clockwise about the centre C.            C
                    vi  Draw the image.
                  b  What is the order of rotational symmetry of the completed pattern?

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