Answer:
sin(θ) = -4/5
Step-by-step explanation:
tan(θ) < 0 means the sine and cosine have opposite signs. The relation between sine and cosine is ...
sin(θ) = ±√(1 -cos(θ)²) = ±√(1 -(9/25)) = ±√(16/25)
We want the negative square root, since the cosine is positive:
sin(θ) = -4/5
