Thank you for posting your question here at brainly. If point B on the pre-image lies at (3, 4), the are the coordinates of B'' on the final is (5, -6). Below is the solutions, I hope the answer helps.
rx-axis ◦ T2,2 (3,4)
= rx-axis ( T2,2 (3,4) )
= rx-axis ( 5,6 )
= (5, -6)