Given that θ terminates in quadrant iii and tanθ 5/12= , find cscθ

now, the square root gives us the +/- version, so.. which is it?  well, the hypotenuse is just a radius unit, is never negative, just the radius unit, so just the absolute value of that or the version 13, so c = 13

now, that we know what the hypotenuse "c" is, well
 
 

25 is obviously the correct answer