Answer:
14.86 feet
Explanation:
We assume the new ramp arrives at the same height as the old one. That height is found using the sine function:
h = 10·sin(18°)
We want to find the ramp length x that will give the same height with an angle of 12°:
h = x·sin(12°)
Substituting for h, we get ...
10·sin(18°) = x·sin(12°)
x = 10·sin(18°)/sin(12°) ≈ 14.863 . . . . feet
The new ramp is about 14.86 feet long.
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Additional comment
The sine relation is ...
Sin = Opposite/Hypotenuse
In this use, we rearrange it to ...
Opposite = Hypotenuse × Sin