Question

1.
The top of a ladder of length 15 m reaches a window 9 m above the ground. What is
the distance between the base of the wall and that of the ladder ?
​

Answer 1

${\boxed{\underline{\tt{\orange{Required \: \: answer \: \: is \: \: as \: \: follows:-}}}}}$

★GIVEN:-

• AC = 15m

• AB = 9m

★TO FIND:-

• BC (distance between base of the wall and ladder)

★FORMULA USED:-

Pythagoras theorem:-

• $\displaystyle\sf{Hypotenuse^2 = Base^2 + Perpendicular^2}$

★SOLUTION:-

In ∆ABC,

We will use pythagoras theorem:-

$: \longrightarrow\displaystyle\sf{AC ^2 = AB^2+BC^2}$

$: \longrightarrow \displaystyle \sf{ {(15)}^{2} = {(9)}^{2} + {BC}^{2} }$

$: \longrightarrow \displaystyle \sf{BC = \sqrt{225 - 81} }$

$: \longrightarrow \displaystyle \sf{BC = \sqrt{144} }$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \displaystyle{ \sf {\bf{ \boxed{ \underline{ \purple{ \huge{BC = 12m}}}}}}}$