Why are the tables symmetric about the diagonal from the upper-left corner to the lower-right? For example, why is the entry in the third row of the second column equal to the entry in the second row of the third column? Would a subtraction table be symmetric about the same diagonal?

(c) the diagram shows the first three shapes of a matchsticks arrangement.first shape = 3second shape = 5third shape = 7given m represents the number of matchstick used to arrange the n'th shape.(i) write a formula to represent the relation between m and n. express m as the subjectof the formula.(ii) 19 matchsticks are used to make the p'th shape. find the value of p.