Question

A 25​-foot ladder is placed against a vertical wall of a​ building, with the bottom of the ladder standing on level ground 18 feet from the base of the building. How high up the wall does the ladder​ reach?

Answer 1

a^2 +b^2 = c^2
a= wall
b = ground (18)
c = ladder (25)
a^2 + 18^2 = 25^2
a^2 + 324 = 625
a^2 = 301
a = 17.349