A ladder of length 6.5m is leaning against a vertical wall. The foot of the ladder is 1.5m from the wall. Calculate the distance the ladder reaches up the wall to 3 significant figures.
(using Pythagoras' theorem) 6.52 = x2+ 1.52 x2= 6.52- 1.52 x2= 42.25 - 2.25 x2 = 40 x = sqrt(40) x = 6.32 (to 3sf) = 6.32m
PB
