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Answer:
20
Step-by-step explanation:
We know that the diagonals are bisected, which means
2x+4 = 6x-8
Subtract 2x from each side
2x+4-2x = 6x-8-2x
4 = 4x -8
Add 8 to each side
4+8 = 4x-8+8
12 = 4x
Divide by 4
12/4 = 4x/4
3 =x
We want to know CF = DB = 2x+4 + 6x -8
CF = 8x-4
= 8(3) -4
= 24-4
= 20