This course teaches both plane and solid geometry. Students develop an understanding of the meaning, nature, and application of mathematical proofs. They also develop mathematical concepts of an arithmetic and algebraic nature and gain an understanding of plane and space relationships. Topics studied include proof and application of theorems about triangles, perpendicular and parallel lines, polygons, and circles. Topics also include construction, measure, transformations, similarity, and proportion, surface area and volume, and trigonometry.