Answer:
Step-by-step explanation:
The set up given will form a right angled triangle with the length of the ladder as the hypotenuse and distance between the the floor and the top of the ladder as the adjacent side to one of the acute angle 45 degrees.
Using one of the trigonometry identity to calculate How high off the ground the top of the ladder. According CAH;
cos 45° = Adjacent/Hypotenuse
cos45° = y/13
y = 13cos45°
y = 9.19ft
The ladder is 9.19ft off the ground