Sum of all angles is 360. There are 8 angles. 360/8 is 45. Exterior and interior angles are supplementary meaning their sum is 180. 180-45 is 135.
Surface area is 62 units ^2
5 x 2 = 10 since there are 2 of these side double it (20)
3 x 2 = 6 since there are 2 of these side double it (12)
3 x 5 = 15 since there are 2 of these side double it (30)
20 + 30 + 12 = 62
Answer : -6
The common difference of a sequence is the value that changes every time the sequence continues.
In your sequence it is seen that 6 is subtracted from each term in order to get to the next in the sequence.
