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Find the 10th term of the arithmetic sequence -x + 9, 4x + 14, 9x + 19, ...

User Gwilym
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1 Answer

3 votes

Answer:

44x + 54

Explanation:

The nth term of an arithmetic sequence is given by :

Tn = a + (n - 1)d

d = common difference = T2 - T1

d = T2 - T1

a = first term = - x + 9

d = 4x + 14 - (-x + 9)

d = 4x + 14 + x - 9

d = 5x + 5

The 10th term:

T(10) = (-x + 9) + (10 - 1)*(5x + 5)

T(10) = - x + 9 + 9(5x + 5)

T(10) = - x + 9 + 45x + 45

T(10) = 44x + 54

Hence, the 10th term is 44x + 54

User Evaldo Bratti
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