The length of line CD is 20. 9
<h3>How to determine the length</h3>
Note that triangle CDY is an isosceles triangle
Using the Pythagoras theorem
Hypotenuse square = opposite square + adjacent square
Hypotenuse = line CD
opposite = 20
Adjacent = 6
Substitute into equation
Make line CD^2 subject by find the square root of the other side
Therefore, the length of line CD is 20. 9
Learn more about Pythagorean theorem here:
brainly.com/question/231802
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