please be patient] $\,\angle 1\,$ and $\,\angle 2\,$ are vertical angles, then $\,m\angle 1 = m\angle 2\ $. DEFINITION parallel lines. Two lines are parallel if and only if they lie in the same plane and do not intersect. Parallel lines are studied in more detail in a future section, Parallel Lines. The symbol â$\,\parallel\,$â is used to denote parallel lines.
Types of Rate Control Drugs. There are three types of rate control medications: 1  Beta Blockers, which slow the heart rate and relax the blood vessels. 2  Examples include Atenolol (Tenormin Â®), Carvedilol (Coregâ¢), Metoprolol (Toprol XLâ¢, Lopressor Â®), and Sotalol (Betapace Â®).
It is used to restore normal heart rhythm and maintain a regular, steady heartbeat. Propafenone is known as an anti-arrhythmic drug. It works by blocking the activity of certain electrical signals in the heart that can cause an irregular heartbeat. Treating an irregular heartbeat can decrease the risk for blood clots, and this effect can reduce your risk of heart attack or stroke.