Answer:
d. 6
Step-by-step explanation:
The product of lengths to the near and far intersection points is the same for both secants:
PB×PA = PD×PC
We can use this relation to solve for x, then use the value of x to find PD.
7×12 = (3x)(7x)
4 = x² . . . . . . . . . divide by 21
2 = x . . . . . . . . . . take the square root
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PD = 3x = 3·2
PD = 6
6x² + 48x + 96
6(x² + 8x + 16)
6(x + 4)(x + 4) is your polynomial fully factored so I'm guessing the binomial you're looking for is (x + 4).
The mode would be 17, it’s the number that appears the most. I’m not rewriting it though