Problema Solution

A 20 foot ladder is leaning against a house. The distance from the bottom of the ladder to the house is 4 feet more than the distance from the top of the ladder to the ground. How far is the bottom of the ladder from the house?

Answer provided by our tutors

let bottom of ladder be x meter from wall

using Pythagoras theorem

x2 + (x+4)2 = 202 

x2 +x2 +8x +16 = 400

2x2 +8x -384 = 0

x2 +4x -192 = 0

(x+16)(x-12)= 0

distance may not negative 

x = 12