In a 2

In a thirteen-sided polygon, the sum of five angles is 1274°, four of the eight angles remaining are equal, and the other four are 18° less than each of the equal angles. Find the angles.

Correct answer:

A =  97.25
B =  79.25

Step-by-step explanation:


1274 + 4·A + 4·B = 180·(13-2)
B = A - 18

4A+4B = 706
A-B = 18

Row 2 - 1/4 · Row 1 → Row 2
4A+4B = 706
-2B = -158.5


B = -158.5/-2 = 79.25
A = 706-4B/4 = 706-4 · 79.25/4 = 97.25

A = 389/4 = 97.25
B = 317/4 = 79.25

Our linear equations calculator calculates it.



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Showing 1 comment:
Dr Math
A = 97.25 (4 angles)
B = 79.25  (last 4 angles)
first 5 angles cannot be determined





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