Answer:
CF = 8.5
Step-by-step explanation:
Given 2 intersecting chords, then
The product of the parts of one chord is equal to the product of the parts of the other chord, that is
CF × DF = BF × EF , substitute values
CF × 14 = 7 × 17
14CF = 119 ( divide both sides by 14 )
CF = 8.5
