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Back to Derive triangle area formula — Problem 5 · Task Set 22

Exercises: Derive the Formula A = (1/2)ab sin(C)

Grade 10·21 problems·~30 min·Common Core Math - HS Geometry·standard·hsg-srt-d-9
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A

Fluency Practice

1.

Find the area of a triangle with two sides of length 4 ft and 9 ft and an included angle of 45°. Use sin⁡(45°)≈0.707\sin(45\degree) \approx 0.707. Round to the nearest tenth.