How this resource helps
All right triangles sharing an acute angle are similar by AA. Their corresponding side lengths scale by the same factor, which cancels in each quotient. Thus opposite/hypotenuse, adjacent/hypotenuse and opposite/adjacent depend on the angle, not triangle size; these define sine, cosine and tangent for acute angles. Standard NC.M2.G-SRT.6: Verify experimentally that the side ratios in similar right triangles are properties of the angle measures in the triangle, due to the preservation of angle measure in similarity. Use this discovery to develop definitions of the trigonometric ratios for acute angles.
What’s Included
- One editable 16:9 PowerPoint with 35 slides and teacher speaker notes on every slide.
- Full standard and all its subparts, unpacking, essential question, learning goals, warm-up, vocabulary and teaching routine.
- Five worked models, guided practice, partner work, five scored independent items, small-group intervention and an open extension.
- Matched blank/completed guided notes, a three-item exit ticket and reflection.
- Editable mathematical diagrams, tables and graphs where relevant. Graphing calculator or spreadsheet activities are included where required by the standard.
Resource details
- Grade / course
- NC Math 2
- Subject and resource type
- Mathematics · PowerPoint Lesson
- Files
- 0 main PDF pages · 35 editable slides · PPTX
- Estimated completion time
- 45–60 minute lesson
- Answer key
- Teacher answer guidance is included in the speaker notes on every slide.
Standard or objective
NC.M2.G-SRT.6 — Verify experimentally that the side ratios in similar right triangles are properties of the angle measures in the triangle, due to the preservation of angle measure in similarity. Use this discovery to develop definitions of the trigonometric ratios for acute angles.
Verify experimentally that the side ratios in similar right triangles are properties of the angle measures in the triangle, due to the preservation of angle measure in similarity. Use this discovery t
Original Saint Pierre Learning Resources lesson aligned to the North Carolina Standard Course of Study for NC Math 2 Mathematics.
Learner directions
Students work through each slide as the teacher directs, completing practice and exit-ticket items.
Teaching suggestions
Project each slide in order. Follow the teacher models, then guide practice as labeled on each slide.