Answer: the height that the ladder reaches is 4 feet.
Step-by-step explanation:
The ladder forms a right angle triangle with the building and the ground. The length of the ladder represents the hypotenuse of the right angle triangle. The height, h from the top of the ladder to the base of the building represents the opposite side of the right angle triangle.
The distance from the bottom of the ladder to the base of the building represents the adjacent side of the right angle triangle.
To determine the height that the ladder reaches, h, we would apply Pythagoras theorem which is expressed as
Hypotenuse² = opposite side² + adjacent side²
12² = 7² + h²
144 = 49 + h²
h² = 144 - 49
h² = 95
h = √95
h = 7.45 feet
