C=2πr=2·π·13≈81.68141
C=81.68
Answer:
3y+3\8
Step-by-step explanation:
1. Let the first integer be represented by: 2k
the second integer by: 2(k+1)
the third integer by: 2(k+2)
and the fourth by: 2(k+3)
Then, 2k + 2(k+2) = 2(k+3) - 6
2k + 2k + 4 = 2k + 6 - 6
4k + 4 = 2k
4 = -2k
-2 = k
Answer: -4, -2, 0, 2
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2. Let the first integer be represented by: 2k+1
the second integer by: 2k+3
the third integer by: 2k+5
and the fourth by: 2k+7
Then, 2k+7 = (2k+1) + (2k+3) + (2k+5) + 2
2k + 7 = 6k + 11
-4 = 4k
-1 = k
Answer: -1, 1, 3, 5
