Question 414921
supplementary angles add up to 180 degrees
 let the smaller angle be  x degrees
then the other is  3x + 40 degrees
their sum should be 180 degrees

so  x + 3x + 40 = 180

==>  4x + 40  = 180

==>   4x = 180 - 40


==>  4x = 140 degrees

==>  {{{4x/4  = 140/4 }}} degrees


==>   x = 45 degrees

smaller angle is 45 degrees