Answer: 8 feet
Step-by-step explanation:
Draw a right triangle and label the sides using the given information. (Drawing below) Use pythagorean theorem to find the missing length:
a^2 + b^2 = c^2
(building)^2 + (missing piece)^2 = (ladder)^2
6^2 + x^2 = 10^2
36 + x^2 = 100. subtract 36
x^2 = 64. square root of both sides
x = 8
