Marissa wants to write an abbreviated set of directions for finding coordinates of a figure reflected across the y-axis. which mapping notation is correct? a. (x, y) --> (-x, y) b. (x, y) --> (x,-y) c. (x, y) --> (-x,-y) d. (x, y) --> (y, x)

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?