The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.

To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:

(y + 2)(y + 6)
(y x y) + (y x 6) + (2 x y) + (2 x 6)
y² + 6y + 2y + 12
y² + 8y + 12

The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c²) is equal to the sum of the two perpendicular sides squared (a² + b²): c² = a² + b² or, solved for c, \(c = \sqrt{a + b}\)

A rhombus is a parallelogram with four equal-length sides. A square is a rectangle with four equal-length sides.

To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(6a)(9ab) - (4a²)(8b)
(6 x 9)(a x a x b) - (4 x 8)(a² x b)
(54)(a¹⁺¹ x b) - (32)(a²b)
54a²b - 32a²b
22a²b