8-3 Trigonometry
Objective
To use the sine, cosine, and tangent ratios to determine side lengths and angle measures in right triangles
Dynamic Activity
Trigonometric Ratios
Lesson Vocabulary
- trigonometric ratios
- sine
- cosine
- tangent
Essential Understanding If you know certain combinations of side lengths and angle measures of a right triangle, you can use ratios to find other side lengths and angle measures.
Any two right triangles that have a pair of congruent acute angles are similar by the AA Similarity Postulate. Similar right triangles have equivalent ratios for their corresponding sides called trigonometric ratios.
Take Note Key Concept: Trigonometric Ratios
sine of
cosine of
tangent of
Table of Contents
- 6-1 The Polygon Angle-Sum Theorems
- 6-2 Properties of Parallelograms
- 6-3 Proving That a Quadrilateral Is a Parallelogram
- 6-4 Properties of Rhombuses, Rectangles, and Squares
- 6-5 Conditions for Rhombuses, Rectangles, and Squares
- 6-6 Trapezoids and Kites
- 6-7 Polygons in the Coordinate Plane
- 6-8 and 6-9 Coordinate Geometry and Coordinate Proofs