If cos θ=(-5/13) and sin θ < 0, what is tan θ ? a. (12/5) b.(13/5) c. (-12/5) d.(√194/5)

If cos θ = (-5/13), then θ  should be in quadrant II or III. The given says  sin θ < 0, so  θ  should be in quadrant III. In this case, tan θ should be equal to  number greater than zero. Hence we get sqrt of (13^2 - 5^2 ) equal to 12. tan  θ should be equal to A 12/5. 

Answer: 900°

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david edward.