6[x+1]=-2[3x+9] please show work will give brainlist

Ibeg you to me 20. a reaction produces 4.93 l of oxygen, but was supposed to produce 1 mol of oxygen. what is the percent yield?

Solve the system of equations using the linear combination method. {4x−3y=127x−3y=3 enter your answers in the boxes.

Fill in the blank 1. a rhombus is a rectangle a) always b) sometimes c) never 2. a square is a quadrilateral a) always b) sometimes c) never 3. a trapezoid is a kite a) always b) sometimes c) never 4. a quadrilateral is a kite a) always b) sometimes c) never 5. a square is a rhombus a) always b) sometimes c) never 6. a parallelogram is a rectangle a) always b) sometimes c) never