Question

Find the measure of angle 1 in each figure

Answer 1

Angles on one side of a straight line will always add to 180°.

$10.\ 180^o-55^o=125^o\\\\11.\ 180^o-111^o=69^o\\\\12.\ 180^o-37^o=143^o\\\\13.\ 180^o-51^o=129^o\\\\14.\ 180^o-40^o=140^o\\\\15.\ 180^o-44^o=136^o$