Answer:
3 ft.
Step-by-step explanation:
When you imagine the sentence, it is a right angled triangle. In this case, it's a Pythagoras Theorem. The formula for it is:
a²(opposite) + b²(adjacent) = c²(hypotenuse)
The building is the opposite, the distance between the foot of the ladder and the building is the adjacent, while the ladder is the hypotenuse.
We have the measurements except for the adjacent. So it will be:
c² - a² = b²
5² - 4² = b²
25 - 16 = b²
9 = b²
√9 = b
b = 3 ft
The answer is 3 ft.
