If two points c and D outside the line BC are known, CA = CB, Da = dB, and the straight line CD intersects AB at O, then point O is the midpoint of AB, and CD is the vertical bisector of ab

There are two reasons
1) The points with equal distance to the two ends of the line segment are on the vertical bisector of the line segment;
2) Two points make a straight line

RELATED INFORMATIONS

1. It is known that C and D are points outside the line AB, and Ca = CB, Da = dB. It is proved that the straight line CD bisects AB vertically Prove with the vertical bisector of line segment
2. If we know the line AB and the points c, D, and Ca = CB, Da = dB, then the line CD is the integral of the line ab______ ．
3. C. D is the point outside the line AB, and Ca = CB, Da = ab Please use the theorem of vertical bisector. No auxiliary line is allowed
4. As shown in the figure, D is a point in the quadrilateral aebc, connecting AD and BD. it is known that Ca = CB, Da = dB and EA = EB. (1) are the three points c, D and E in a straight line? Why? (2) If AB = 24, ad = 13, CA = 20, what is the length of CD?
5. As shown in the figure, (1) (2) Ca = CB, Da = dB, prove that CD is the vertical bisector of ab
6. It is known that, as shown in the figure, CA = CB
7. As shown in the figure, CA = CB, Da = dB
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