Answer: 2.1 miles
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Explanation:
A diagram is optional, but I find it helps sometimes. The diagram is shown below.
Opposite the 10 degree angle is h. So we consider h the opposite side.
The hypotenuse is 12. The hypotenuse is always opposite the 90 degree angle.
Apply the sine ratio to solve for h
sin(angle) = opposite/hypotenuse
sin(10) = h/12
12*sin(10) = h
h = 12*sin(10)
h = 2.08377813200317 which is approximate
h = 2.1 miles is the plane's altitude which is also approximate
Side note: 2.1 miles is equal to 11,088 feet (multiply by 5280 to convert from miles to feet).
