What is the opposite number of -1 1/2

Solve the triangle. a = 21°, c = 105°, c = 5

(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.

Which of the following represents the length of a diagonal of this trapezoid?