Question 1159759


{{{tan (x)=-1}}}->tan is negative in quadrant II and IV 

{{{x=tan^-1(-1)}}}

{{{x=-pi/4}}} (result in radians) 

{{{x=-45}}}° 



solution in quadrant II =>{{{180-45=135}}}°
solution in quadrant IV =>{{{360-45=315}}}°