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Let's call the missing altitude 'x'.
</span><span>✦ To find the plane's altitude, find the tan of 30 degrees. The side opposite is going to be x, while the side adjacent is going to be 4.4 miles.
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<span>✦ We usually write altitude in feet.
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Answer: 2.54 * 5280 ~ <span>
13,400 ft
</span><span>Hope that helps! ★ If you have further questions about this question or need more help, feel free to comment below or leave me a PM. -UnicornFudge aka Nadia</span>
The perimeter of an object is equal to its sides added up. Because this is a triangle, it will have 3 equal sides. Since the triangle has 3 equal sides, its perimeter will be equal to one of its side lengths * 3.
Because the perimeter will be equal to one of its side lengths * 3, x is equal to one of the triangle's side lengths.