Given that $\cos x =-3/4$ and $90^\circGiven that $\;\cos x =-\frac{3}{4}\,$ and $\,90^\circ<x<180^\circ,\,$ find $\,\tan x\,$ and $\,\csc x.$
This question is quite unusual from the rest of the questions in the chapter, can someone please explain how this question is solved? I tried Pythagorean Theorem, but no luck. Is it possible to teach me how to use the circle diagram?

As $90^\circ< x<180^\circ,\tan x <0,\sin x>0$
So, $\sin x=+\sqrt{1-\cos^2x}=...$
$\csc x=\frac1{\sin x}= ... $
and $\tan x=\frac{\sin x}{\cos x}=...$
