Asap i'm ! the measures of the angles of any triangle always add up to 180˚. polygon xyz is a triangle. which of the following is valid base on deductive reasoning? a) the measures of angles x and y add up to 90˚. b) xyz is an isosceles triangle. c) the sum of the measures of angles x, y, and z add up to 180˚. d) angle z is an obtuse angle. (i don't know the answer for this one)