Answer: the top of the ladder is 20ft below the ground.
Step-by-step explanation:
The ladder makes an angle, θ with the ground thus forming a right angle triangle with the wall of the house.
The length of the ladder represents the hypotenuse of the right angle triangle.
The ground distance between the base of the house and the base of the ladder represents the adjacent side of the right angle triangle.
Therefore, to determine the height at which the ladder rest on the building, x, we would apply Pythagoras theorem which is expressed as
Hypotenuse² = opposite side² + adjacent side²
25² = x² + 15²
625 = x² + 225
x² = 625 - 225 = 400
x = √400 = 20 ft
