David M. answered 01/25/21
Dave "The Math Whiz"
First, we must determine what quadrant ø is in. We know that tangent is negative in QII & QIV. We also know that sine is negative in QIII & QIV. This shows that in order for the sine of ø and tangent of ø to both be negative, ø must be in QIV. If we make a right triangle with -21 on the opposite side of ø and +20 on the adjacent side, we can find that the hypotenuse is hyp. = √(-21)2 + (20)2--->hyp. = 29.
sinø = opp./hyp.
cosø = adj./hyp.
tanø = opp./adj.
cscø = hyp./opp.
secø = hyp./adj.
cotø = adj./opp.
I'll leave the rest for you.
Hope this helps!