Answer:
The exact value of sin A is opp/hyp = -12/13
Step-by-step explanation:
If A is in Quadrant IV then the "opposite side" is negative and the "adjacent side" is positive. Since sec A = hyp / adj = 13 / 5 and since opp^2 + adj^2 must add up to hyp^2, Therefore y = √(hyp^2 - adj^2), or
y = -√(13^2 - 25) = -√144 = 12.
The exact value of sin A is opp/hyp = -12/13
