If Cot θ = -Square Root of 15/7, use the fundamental identities to find Cosθ > 0.

Answer 1

If cot Ø = =√15/7 then
tan Ø = -7/√15

you want tangent to be negative and cosine to be positive, ---> must be in IV
construct you triangle in quad IV
by Pythagoras, the hypotenuse is 8
and cos Ø = √15/8