Question

a ladder,6.5m long,rests against a vertical wall. if the foot of the ladder is 2.5m from the foot of the wall,find upto how much height does the ladder reach?

Answer 1

by Pythagoras theorem we can find.let ac be the length of the ladder.then ac=6.5cm.then let bc be the length from the wAll to the foot.then bc=2.5cm.then the height of the wall is ab=? now to have ac=6.5cm,bc=2.5cm.we forms a right angled triangle.thus by applying Pythagoras theorem. ac^2=ab^2+bc^2. ab^2=ac^2-bc^2.ab^2=(6.5)^2-(2.5)^2
ab^2=42.25-6.25
ab^2=36
ab=√36
ab=6cm.

hope it will help you