Question

A 15 metre long ladder is placed against the wall in such a way that the foot of the ladder is 9 M away from the wall up to the what height does the ladder reach the wall

Answer 1

Length of ladder=15m
Distance between foot of ladder and wall=9m
Let the height of wall be Xm
(15)² =x² +(10)²
225=x² +100
225-100=x²
125=x²
X=root of 125
X=5

Answer 2

Heya...
Here is your answer ----

_____________________________

In the given figure, ABC is a Right-angled Triangle right Angled at B.
AC represents the ladder, AB the wall and BC the distance between their foot.

Now, according to Pythagoras Theorem,

(Hypotenuse)^2 = (Perpendicular)^2 + (base)^2

=> (15)^2 = (P)^2 + (9)^2

=> (P)^2 = (15)^2 - (9)^2

=> (P)^2 = 225 - 81

=> (P)^2 = 144

=> P = √(144)

=> P = √(2×2×2×2×3×3)

=> P = 2×2×3

=> P = 4×3 = 12

Hence, the height of wall where the ladder will get placed = AB = 12 m

HOPE IT HELPS......!!!!