BitWithBite
Mathematics Worksheet
📏 Law of Sines
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After this worksheet you can
Apply a/sin A = b/sin B = c/sin C.Find a missing side or angle.Use the triangle angle-sum.Recognise when the Law of Sines applies.📚 Quick Recap
The Law of Sines connects the sides and angles of ANY triangle, not just right triangles — a powerful tool for solving triangles when you don't have a 90° angle to work with.
🧠 Section A · Concept Check ● BEGINNER 4 × 1 = 4
1A triangle has A=50°, B=60°, a=12. Side b is about:
2A triangle has angles 55° and 65°. The third angle is:
3A triangle has B=90°, C=30°. Angle A is:
4The Law of Sines uses:
🧮 Section B · Problem Solving ● INTERMEDIATE 2 + 3×3 = 11
5Law of Sines: a/sin A = b/sin B = .
6The angles of a triangle sum to .
7A triangle has A=50°, B=60°, a=12. Find side b.
8A triangle has A=35°, a=7, c=10. Set up the proportion to find angle C.
9A triangle has angles 55° and 65°. Find the third angle.
🚀 Section C · Challenge ● CHALLENGE 5
10A triangle has B=90°, C=30°. Find angle A.
💭 Reflection — the most useful thing I learned:
A ___/4 B ___/11 C ___/5 Total ___/20
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✂ answer key — fold or cut before handing out
1-A 2-A 3-A 4-A | 5 c/sin C 6 180° 7 = 12·sin60°/sin50° ≈ 13.57 8 = 7/sin35° = 10/sin C 9 = 60° | 10 = 60°