Answer:
12/13
Explanation:
The length of the segment from the origin to the terminal point is ...
r = √((-5)² +12²) = √169 = 13
The sine of the angle is the ratio of the y-coordinate to this distance
sin(θ) = y/r = 12/13
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Additional comment
The other trig functions are ...
cos(θ) = x/r = -5/13
tan(θ) = y/x = -12/5
This is a 2nd-quadrant angle, where the sine is positive, but the cosine and tangent are negative.