-80° is in quadrant IV
become familiar with the CAST rule and these problems
are really easy.
The CAST rule tells you where the primary trig ratios are positive
using that:
cos(-80deg)>0 and tan(-80deg)<0
What signs are cos(-80deg)and tan(-80deg)?
cos(-80deg)>0 and tan(-80deg)<0
They are both negative
They are both positive
cos(-80deg)<0 and tan(-80deg)>0
1 answer