Question

A ladder $10m$long was rested along a wall such that its top touched the wall at a height of $8m$ from the ground. How far is the foot of the ladder from the wall?

Answer 1

Find distance between the foot of the ladder and the wall:

Lets draw the required diagram:

Now, applying Pythagoras Theorem,

$\Rightarrow$ ${\left(10\right)}^2={\left(8\right)}^2+{\left(AB\right)}^2$

$\Rightarrow$ $100=64+{\left(AB\right)}^2$

$\Rightarrow$${\left(AB\right)}^2=100-64$

$\Rightarrow$${\left(AB\right)}^2=36$

$\Rightarrow$ $AB=\sqrt{36}$

$\Rightarrow$ $\left(AB\right)=6cm$

Thus, the foot of the ladder is $6cm$ far from the wall.