Answer:
The top of the ladder is 19.6 ft up the wall.
Step-by-step explanation:
We have a 20-ft ladder leaned against a wall. The distance from the wall to the base of the ladder is 4 ft.
We have to calculate how far up the wall of the house is the top of the ladder.
To calculate this we use the Pithagorean theorem, where:
[tex]L^2=b^2+h^2[/tex]
L: length of the ladder (20 ft), b: distance between the base of the ladder and the wall (4 ft) and h: height of the ladder (x, to calculate). See figure attached.
Then we can write:
[tex]20^2=4^2+x^2\\\\x^2=20^2-4^2=400-16=384\\\\x=\sqrt{384}\approx 19.6[/tex]
The top of the ladder is 19.6 ft up the wall.
