SOLUTION: You are given the measure of each interior angle of a regular n-gon. Find the value of n.
12.) 128 4/7 degrees
i know you must use the formula
n x (n-2) x 180
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-> SOLUTION: You are given the measure of each interior angle of a regular n-gon. Find the value of n.
12.) 128 4/7 degrees
i know you must use the formula
n x (n-2) x 180
Log On
You can put this solution on YOUR website! Actually, you have an extra factor of n in the numerator of your formula. The formula for the measure of the interior angles of a regular n-sided polygon is:
.
Since you are given that the measure of the interior angle of your regular polygon is 128 4/7 degrees, you need to set your formula equal to this measure and then solve for n. Just as a sanity check, since the denominator of the fraction in the angular measure is 7, I expect that the number of sides will turn out to be 7 or some multiple of 7.
Multiply both sides by n: (I added the whole number part of the angle measure and the fractional part because this formula system won't render mixed numbers)
Distribute:
Put the variable terms on the left, and the constants on the right:
Rather than converting everything to fractions, just multiply both sides by the denominator of 7: