The Triangle and its properties | Exercise 6.5

Question

Q3) A 15 m long ladder reached a window 12 m high from the ground on placing it against a wall at a distance a. Find the distance of the foot of the ladder from the wall.

Solution
Transcript

Hello guys, welcome to lido homework today we're looking at question numbers. three which is a 15-meter long ladder reached the window 12 meters high from the ground and placing it against the wall at a distance a find the distance at the foot of the the ladder from the wall so here's what we're going to use is your Pythagoras theorem so Pythagoras Theorem is h square which is hypotenuse square okay so hypotenuse square is equal to sorry is equal to a square which is one side plus b square which is another so let's calculate it hypertension this was given to us as 15 square so 15 square is equal to square so one side is 12 row 12 meters or 12 squared Plus, the square 15 square is 225 225 is equal to 144 Plus the square next step that we'll be doing is We'll subtract them so a square is equal to 225 minus 144 taking 140 for this side okay so 225 minus 144 will will give you the answer as 81 so a square will be equal to 81 now you just need to find the square the root of 81 so the square root of 81 is obviously 9 therefore a will be equal to 9 meter thank you so much guys, please like the video and subscribe to the channel

Accepted Answer

Solution 3:

Let AC be the ladder, and A be the window

$h^2=\ b^2+p^2$

$\left(15\right)^2\ =\ \left(a\right)^2\ +\ \left(12\right)^2$

$225\ -\ 144\ =\ a^2$

$81\ =\ a^2$

$\sqrt{81}\ =\ a$

a = 9

The Triangle and its properties | Exercise 6.5

Chapters in NCERT Solutions - Mathematics, Class 7

Exercises in The Triangle and its properties

Question 5