Answer:
15
Explanation:
53
Let x = 1, 2, 3, 4, and add the values.
3 + (1^2 + 2 * 1) + (2^2 + 2 * 2) + (3^2 + 2 * 3) + (4^2 + 2 * 4) =
= 3 + 3 + 8 + 15 + 24
= 53
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