3 years ago

find the sum of the first 20 terms of an arithmetic sequence with a first term of -14 and a comman difference of 4

Mathematics

1 answer:

timama [110]3 years ago

7 0

Answer:

480

Step-by-step explanation:

Sn = n÷2 × (2a + (n-1)d)

n = 20 a = -14 d = 4

S20 = 10 × (-28 + 19 × 4) = 480

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Read 2 more answers

find the sum of the first 20 terms of an arithmetic sequence with a first term of -14 and a comman difference of 4​

find the sum of the first 20 terms of an arithmetic sequence with a first term of -14 and a comman difference of 4