Question

A 21 foot ladder is placed against a vertical wall of a building, with the bottom of the ladder standing on level ground if 14 foot from the base of the building. How high up the wall does the ladder reach

Answer 1

15.65 foot

Explanation:

Pythagoras theorem can be used

a² + b² = c²

a being 14
b being unknown ( x )
c being 21

hence,

14² + x² = 21²
196 + x² = 441

x = √245

= 15.65 foot (answer)