What will be the answer for 9÷3(2+1)?​

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Match the equivalent expressions. x - 3y + 12 12 - 3y - 2x + x + 2x 3x + 2y - 2x + y + 12 3y + 12 3x + y - 12 4y + 3y + 3x - 6y - 10 - 2 x + 3y + 2x - 3x + 7 + 5 x + 3y + 12 5 + 2y + 7x - 4x + 3y - 17

Cd is the perpendicular bisector of both xy and st, and cy=20. find xy.