2-3 simplify expression

Use the diagonals to determine whether a parallelogram with vertices u(2,−2), v(9,−2), w(9,−6), and x(2,−6) is a rectangle, rhombus, or square. give all the names that apply.

What is the 12th term of b(n)=-4-2(n-1)

Which represents the solution set of the inequality 5x-9 < 21? a. x < 12/5 b. x > 12/5 c. x > 6 d. x < 6