Answer:
5/13
Step-by-step explanation:
Finding the missing side :
- opposite side² + adjacent side² = hypotenuse² (Pythagorean)
- (12)² + adjacent side² = (13)²
- adjacent side² = 169 - 144
- adjacent side² = 25
- adjacent side = √25
- adjacent side = 5
Taking the cos ratio :
- cosθ = adjacent side / hypotenuse
- cosθ = 5/13
