Answer:
78.5°
Explanation:
We solve for the above question, using the formula for the Trigonometric function of Cosine
cos θ = Adjacent/Hypotenuse
Adjacent = The distance between the house and the base of the ladder = 4 feet
Hypotenuse = Length of the Ladder = 20 feet
Hence,
cos θ = 4/20
θ = arc cos(4/20)
θ = 78.463040967°
Approximately = 78.5°
Therefore, the angle that the ladder makes with the ground is 78.5°