In mathematical logic, the Law of Detachment says that if the following two statements are true:
( 1 ) If p, then q.
( 2 ) p
Then we can derive a third true statement:
( 3 ) q.
In our question, we have
( 1 ) If 0º< A <90º, then A is an acute angle.
( 2 ) The measure of A is 58º.
Then, from the first statement, we can affirm
( 3 ) A is an acute angle.
