Answer:
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DC is the radius and its length is:
DC is the perpendicular bisector of EF. Hence the half of the segment EF is the leg of a right triangle with the hypotenuse of EC = DC = 70 and other leg of 50 units.
Using the Pythagorean theorem, find the length of EF:
- (EF/2)² = 70² - 50²
- (EF/2)² = 2400
- EF/2 = √2400
- EF/2 = 20√6
- EF = 40√6