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(n+20)*2 = 99.2
distribute
2n + 40 = 99.2
subtract 40 from each side
2n = 59.2
divide each side by 2
n = 29.6
This conjecture is false, A and C don't have to be complementary angles.
Let Angle A be 100 and Angle B be 80 degrees. They are supplementary (sum of 180).
Let Angle C be 100 and Angle B is still 80 degrees. They are supplementary.
However, Angle A and Angle C are not complementary (sum of 90).
10. This is because 3 evenly goes into 30 without a remaining fraction
