Answer:
-24/5
Explanation:
The solution to the problem is as follows:
cscx < 0 means 1/sinx < 0, or sinx < 0.
sinx = -3/5 because you're dealing with a 3-4-5 triangle, and we established
sinx is negative.
sin2x = 2sinxcosx = 2*-3/5*4/5 = -24/25
cos(2x) = cos^2(x) - sin^2(x) = 16/25 - 9/25 = 5/25 = 1/5
tan2x = sin2x / cos2x = -24/5