How do i do them ? i don't know if i started them right.

Find the area of the regular hexagon if a side is 20 cm.

Ade and abc are similar. which best explains why the slope of the line between points a and d is the same as the slope between points a and b?

(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.