Answer: 4.9
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Step-by-step explanation:
Focus entirely on the triangle on the right side. The other parts of the drawing are not necessary. In my opinion, they are distracting filler.
Refer to the diagram below.
We have an unknown adjacent side, let's call it x, that's along the horizontal part of the triangle.
The hypotenuse however is known and it is 19 ft
We use the cosine ratio to tie the two sides together
cos(angle) = adjacent/hypotenuse
cos(75) = x/19
19*cos(75) = x
x = 19*cos(75)
x = 4.9175618569479 which is approximate
x = 4.9
The base of the ladder is roughly 4.9 feet away from the base of the house.
Side note: make sure your calculator is in degree mode.