A 15-foot ladder is leaning against a building, with the base of the ladder 3 feet from the building. how high up on the building will the top of the ladder reach?
here we basically use Pythagoras' theorem looking at the picture above, I have drawn it out to make it clearer. Pythagoras' theorem is : a^2 + b^2 = c^2 in this case we are trying to find the height so we would do the hypoteneuse ( longest side ) minus the smaller side so:
15^2 - 3^2 = 225 - 9 =216 now finally we would square root 216 =14.7ft
