The ladder resting against the house forms a triangle similar to the one in the image below
To answer this question you must use Pythagorean theorem
[tex]a^{2} +b^{2}=c^{2}[/tex]
a and b are the legs (the sides that form a perpendicular/right angle)
c is the hypotenuse (the side opposite the right angle)
In this case...
a = x
b = 4
c = 20
^^^Plug these numbers into the theorem
[tex]x^{2} +4^{2} =20^{2}[/tex]
solve for x
[tex]x^{2}[/tex] + 16 = 400
[tex]x^{2}[/tex] = 384
x = 8√6
or
x ≈ 19.5959....
Hope this helped!
~Just a girl in love with Shawn Mendes
