Influence line of Ma, Rd, and Qd^r<br/><img src="https://media.cheggcdn.com/media%2Fe38%2Fe381cbb8-e942-41c7-a578-91cec9242513%2Fimage.png" alt="Example 16-16 Influence line of MA. RD and QB P-1 4m 7n 3m×6=18m" aria-describedby="d3f"/>Example 16-16 Influence line of MA. RD and QB