Answers:
A, B, D, E
Nearly everything except choice C is true.
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Step-by-step explanation:
- Choice A is true because sine = opposite/hypotenuse.
- Choice B is true as well because cosine = adjacent/hypotenuse
- Tangent is opposite/adjacent. The 4/9 should be 9/4. Therefore, choice C is false. If beta was theta, then tan(theta) = 4/9 would be true.
- Choice D is true because of the pythagorean theorem a^2+b^2 = c^2.
- Choice E is true because tan = opposite/adjacent, and the 9 and 4 are in the correct order (see choice C).