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®).
Inotropic Drugs: What You Need to Know. Positive inotropic drugs improve heart function in cases of heart failure (when the heart is not pumping well enough), heart attacks and various types of heart disease. Doctors very often prescribe one of the digitalis compounds, digoxin, for patients with heart failure.