Answer:
c = 8
Explanation:
Use synthetic division here; it's the fastest approach.
Given that (x + 2) is a factor, take -2 and use this as the divisor in synthetic division:
-2 4 c 1 2
-8 (-2c+ 16) (4c-34)
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4 (c - 8) (-2c + 17) 4c - 32
The remainder, 4c - 32, must equal zero if (x + 2) is a factor.
Then 4c - 32 = 0, and c = 8