Answer:
5/13
Step-by-step explanation:
Sine is equal to the length of the opposite side divided by the length of the hypotenuse, while cosine is equal to the length of the adjacent side divided by the hypotenuse. Since you know that the opposite side has length 12 and the hypotenuse has length 13, you can use the pythagorean theorem to find that the length of the third (adjacent) side is [tex]\sqrt{13^2-12^2}=5.[/tex] Therefore, the cosine of that angle is 5/13. Hope this helps!
