Worksheets — Set 2

Geometry · Similarity and right-triangle trigonometry

Print and write your answers. Use diagrams to show thinking.

Warm-up

1. Similar triangles: sides 6, 7, and 8. Scale factor? ___ 2. If ΔABC ~ ΔDEF and AB/DE = 5, find BC/EF = ___ 3. Right triangle: opposite=6, hypotenuse=8. sin θ = ___

_See printable PDF for diagram._

Written practice

1. Similar triangles: sides 5, 6, and 7. Scale factor? ___ 2. If ΔABC ~ ΔDEF and AB/DE = 4, find BC/EF = ___ 3. Right triangle: opposite=5, hypotenuse=7. sin θ = ___ 4. Find missing side using tan 45° = ___ 5. Dilation scale factor 1.7. Image length? ___ 6. Explain why the triangles are similar. 7. Similar triangles: sides 8, 9, and 10. Scale factor? ___ 8. If ΔABC ~ ΔDEF and AB/DE = 7, find BC/EF = ___

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More written practice

1. Right triangle: opposite=8, hypotenuse=10. sin θ = ___ 2. Dilation scale factor 2. Image length? ___ 3. Similar triangles: sides 11, 12, and 13. Scale factor? ___ 4. If ΔABC ~ ΔDEF and AB/DE = 10, find BC/EF = ___ 5. Right triangle: opposite=11, hypotenuse=13. sin θ = ___ 6. Dilation scale factor 2.3. Image length? ___

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Patterns and rules

1. Similar triangles: sides 22, 23, and 24. Scale factor? ___ 2. If ΔABC ~ ΔDEF and AB/DE = 21, find BC/EF = ___ 3. Right triangle: opposite=22, hypotenuse=24. sin θ = ___

_See printable PDF for diagram._

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Parent tip: Set up proportions from similar triangles