Question

The foot of a ladder is $6m$ away from a wall and its top reaches a window $8m$ above the ground. If the ladder is shifted in such a way that its foot is $8m$ away from the wall, to what height does its top reach?

• A. $6$m
• B. $4$m
• C. $5$m
• D. $3$m

Answer 1

The correct option is A $6m$

Let the length of the ladder is $l$ i.e $(BC=DE).$ Since AED is right-angle triangle with $l$ as hypotenuse.

so $l^2=8^2+6^2$.

so, $l=10$

length of ladder will remain same, In right-angled triangle BAC, we have

$B{C}^2=A{C}^2+A{B}^2$

${10}^2=x^2+8^2$ [$\therefore$ BC = length of ladder]

so, $x^2={10}^2-8^2=36$

$\therefore x=6$

Hence, height is $6m$