High School Geometry
Domain Similarity, Right Triangles, and Trigonometry
Cluster Define trigonometric ratios and solve problems involving right triangles
Standard Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.

G-SRT.C.6. Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.