Let us name the points first.
M (4, 3)
N (3, 2)
O (2, 1)
P (1, 0).
Now, reflections of these points in x-axis can be written as:
M' (4, -3)
N' (3, -2)
O' (2, -1)
P' (1, 0)
Therefore, according to the question:
a = 4, b = 3, c = 2, and d = 1
Hence,
a +
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b2 +
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c3 +
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d4 = 4 + 9 + 8 + 1 = 22.