A ladder is leaning against a building.The distance from the bottom of the ladder to the building is 6ft shorter than the length of the ladder.How high up the side of the building is the top of the ladder if that distance is 3ft less than the length of the ladder

Respuesta :

Answer:

15 ft

Step-by-step explanation:

Hi, the illustration for the problem is a right triangle with:

hypotenuse (C)= the length of the ladder = L

horizontal side(A) = distance from bottom of the ladder to the building = L - 6

vertical side(B) = distance from the top of the ladder to the bottom of the building = L - 3

So, we can use Pythagoras formula:

A2 +B2= C2

(L – 6 )² + (L-3)² = L²

L²-12L+36+L²-6L+9 =L²

L2 -18L+45 =0

APPLYING QUADRATIC FORMULA WE OBTAIN:

L =15 OR L=3

If L=3

Vertical side = L-3 = 0 (Length can´t be 0)

So L=15