West Bengal Board Solutions for Chapter: Geometrical Concepts Based on Different Instruments of Geometry Box., Exercise 17: Exercise 17

                                     $\angle DEF=45°$                                                                  $\angle GHI=60°$

Let's measure the angles with protractor and verify.

                                     $\angle DEF=45°$                                                          $\angle GHI=60°$

Using set square, let us draw $90°$ angle and verify with protractor.