Please help asap for a test

2340

Step-by-step explanation:

sum of interior angles = (n-2)×180, where n is the number of sides

                                     =(15-2)×180

                                     =13×180

                                     =2340

Each interior angle = sum of interior angles / number of sides of the polygon

                                =2340/15

                                =156

Sum of exterior angles = 360

Each exterior angle= sum of exterior angles/number of sides

                                = 360/15

                                =24

-6 + 3 = 3 - 6