Problem 20 of 7
Derive triangle area formula for obtuse included angle obtuse B with sides a and c.
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handle exterior altitude while preserving sine relationship.
Hidden until you reveal it.
Handle exterior altitude while preserving sine relationship for obtuse included angle.
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Your answer is equivalent to the expected form.
Walkthrough
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1. Draw exterior altitude for the obtuse triangle.
2. Relate the altitude to the supplement of the obtuse angle.
3. Use sin(180-theta)=sin(theta).
4. Substitute into base-height area.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Claiming formula only works for acute triangles.