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              5.  If two complementary angles are in the ratio 1 : 3, find the measure of angles.

              6.  One of two supplementary angles is 24° more than the measure of the smaller one. Find their
                 measures.

              7.  An angle is two-third of its complement. What is the degree measure of the angle?
              8.  One-third of the supplement of an angle is equal to 10° more than its complement. Find the angle.
              9.  Find the value of x in the following figures:
                 (a)                                              (b)
                                                                       D                         C
                                                                                 7x + 22°
                                                                                8x         3x – 4°
                      x + 3° x – 1°                                    A             O            B

                        x + 1°

             10.  In the given figure, ∠XYZ = 64° and XY is produced to a point P. If ray YQ bisects ∠ZYP, find ∠XYQ
                 and reflex ∠QYP.

                                                           Z         Q

                                                            64°
                                                       X        Y         P



                    Knowledge Desk

                  Our country is situated to the north of the equator between 8°4' (eight degree four minutes) north to
                  37°6' (Thirty-seven degree six minutes) north latitude and 68°7' (Sixty-eight degree seven minutes) east
                  to 97°25' (Ninety-seven degree twenty-five minutes) east longitude.
                                                         1
                  (Q 1 degree = 60 minutes & 1 minute =      degree)
                                                         60
            Pair of Lines


            Intersecting Lines

                                                                                                                    l 1
            When two lines in a plane intersect at a point, then these lines are called
            intersecting lines and the point at which they intersect is called the point of                 O
            intersection. In the figure, l  and l  are two intersecting lines and O is the point                    l 2
                                           1
                                                 2
            of intersection of lines l  and l .
                                      1
                                             2
            There are some examples of intersecting lines in day-to-day life.
                                                                                            Quick Check
                                                                                         Find  some  examples  from
                                                                                         your surroundings where lines
                                                                                         intersect at right angles and
                                                                                         make a list here.


            Sometimes when two lines intersect, they meet at 90° angle.                     Remember
            These intersecting lines are called perpendicular lines.                Two  straight  lines  in  a  plane
                                                                                    intersect exactly at one point.


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