4 Analytic Geometry and
Trigonometry
Geometry is divided into two branches: analytic geometry and trigonometry.
Trigonometry began as the computational component of geometry. For instance,
one statement of plane geometry states that a triangle is determined by a side
and two angles. In other words, given one side of a triangle and two angles in
the triangle, then the other two sides and the remaining angle are determ ined.
Trigonometry includes the methods for computing those other two sides. The
remaining angle is easy to find since the sum of the three angles equals
180 degrees (usually written as 180
). Analytic geometry is a branch of algebra
that is used to model geometric objects—points, (straight) lines, and circles being
the most basic of these. ...