A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).

The area of a parallelogram is equal to its length x width:

a = l x w
a = a x b
a = 4 x 8
a = 32

The volume of a cylinder is πr²h:

v = πr²h
v = π(9² x 9)
v = 729π

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.

(8a)(2ab) + (8a²)(3b)
(8 x 2)(a x a x b) + (8 x 3)(a² x b)
(16)(a¹⁺¹ x b) + (24)(a²b)
16a²b + 24a²b
40a²b

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 + 1)
(y x y) + (y x 1) + (2 x y) + (2 x 1)
y² + y + 2y + 2
y² + 3y + 2