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The measure of each interior angle of a regular polygon can be expressed as x-5 and the number of sides by 10x. Determine the following the number of degrees in each exterior angle

User Reflection
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1 Answer

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Answer:

0.1948° in each exterior angle

Explanation:

The exterior angle measure is 360° divided by the number of sides. Here, that is 10x, so the exterior angle is ...

360°/(10x) = 36°/x

The measure of the interior angle is the supplement of the exterior angle, so we have ...

x -5 = 180 -(36/x)

x(x -5) = 180x -36 . . multiply by x

x^2 -185x = -36 . . . . . subtract 180x

x^2 -185x +8556.25 = -36 +8556.25 . . . . complete the square

(x -92.5)^2 = 8520.25

x -92.5 ≈ ±92.3052

x ≈ 184.8052 or 0.19480

It does not make any sense for the number of sides to be 10·0.1948 = 1.948, so we assume the number of sides is 184.8052·10 = 1848.

Then the number of degrees in each exterior angle is ...

36°/184.8052 = 0.1948