What is the value of x? PLZ HELP ME< DON'T UNDERSTAND

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x = ?

A right triangle with vertices labeled as A, B, and C. Side C B is the base, and the top vertex is A. Side A B contains a midpoint D. A line segment drawn from C to D bisects angle A C B into two parts labeled as A C D and B C D. Angles A C D and B C D are marked with single arc. Side A C is labeled as 3. Base C B is labeled as 4. Segment A D is labeled as 2.25. Segment B D is labeled x.