three years ago the ratio of the ages of A and B was 4:3 .Three years hence the ratio of the ages will be 11:9 .find the present age of A and B​

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?