Simplify the equation and write the answer without negative exponents

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Sam makes his sales calls according to a pattern. he travels either north or south depending on the calendar. some of his past trips were as follows: on february 17, april 24, june 10, september 19, and november 3 he drove north. on february 28, may 25, august 22, november 20, and december 18, he drove south. describe sams' pattern. in which direction will sam drive on oct4 and oct 24?

Graph red beads cost $1 an ounce and gold beads cost $3 an ounce. juanita wants to purchase a 12-ounce mixture of red and gold beads that she can sell for $2 an ounce. the solution of the system shows the number of beads needed for juanita to break even. x + y = 12, x + 3y = 24 how many ounces of red beads will juanita buy to break even? how many ounces of gold beads will she buy?