You can
put this solution on YOUR website!let distance of foot of ladder be x
height will also be x
ladder length = 40
The ladder ,ground and the wall form a right triangle
ground distance = leg2
height at which ladder touches
Hypotenuse = ladder length
Pythagoras theorem states that
Hypotenuse ^2= leg1^2+leg2^2
40^2=x^2+x^2
1600=2x^2
1600/2= x^2
800=x^2
take the square root
x=28.285 feet