Use the premises and conclusion to answer the questions. premises: if a triangle has an angle with a measure more than 90°, then the triangle is an obtuse triangle. the measure of an angle in △abc is 110°. conclusion: △abc is an obtuse triangle. is the argument valid? why or why not? the argument is not valid because the premises are not true. the argument is valid by the law of detachment. the argument is valid by the law of syllogism. the argument is not valid because the conclusion does not follow from the premises.