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OpenStax, Algebra and Trigonometry 2e §10.2 Non-right Triangles: Law of Cosines · Exercise 75 · Trigonometry · Laws of sines & cosines

Non-right Triangles: Law of Cosines · Exercise 75

The four sequential sides of a quadrilateral have lengths 4.5 cm, 7.9 cm, 9.4 cm, and 12.9 cm. The angle between the two smallest sides is 117°. What is the area of this quadrilateral?

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OpenStax, Algebra and Trigonometry 2e · §10.2 Non-right Triangles: Law of Cosines · Exercise 75

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