Angle: The measure of the opening between two intersecting lines is called an angle. Unit: The unit of angle is radians or degrees. Angle formula: There are different types of formulas for calculating ...

Parallel lines close parallel lines Lines which never meet and stay the same distance apart. Parallel lines are indicated by a pair of arrows. are two or more straight lines that remain the same ...

Learn the essential definitions of the parts of a circle. A secant line to a circle is a line that crosses exactly two points on the circle while a tangent line to a circle is a line that touches ...