subtracting polynomial expressions

Question

Ms. Keller wants to design the garden so that it resembles a square contained within a rectangle. The modeled area of the square is given by the expression 4x2+4x−2 , and the area of the rectangle is given by the expression 10x2−9

. Ms. Keller wants to figure out the area of the rectangle minus the area of the square in order to determine what area she has available for planting some plants. What expression represents the area Ms. Keller will have available for planting?

Answer 1

rectangle - square

10x² - 9 - [4x² + 4x - 2] = ?