Question 648063
find other fundamental identities if tan theta=8/15 and sec theta <0
tan>0 in quadrants I and III
sec<0 in quadrants III and IV
so, we are working with a reference angle and right  triangle in quadrant III
opposite side=-8
adjacent side=-15
hypotenuse=&#8730;(8^2+15^2)=&#8730;(64+225)=&#8730;289=17
..
fundamental identities:
sin theta=-8/17
cos theta=-15/17
tan theta=8/15
csc theta=-17/8
sec theta=-17/15
cot theta=15/8