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.

(2a)(5ab) + (7a²)(6b)
(2 x 5)(a x a x b) + (7 x 6)(a² x b)
(10)(a¹⁺¹ x b) + (42)(a²b)
10a²b + 42a²b
52a²b

The formula for circumference is circle diameter x π:

c = πd
c = 16π

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 + 8)(y + 5)
(y x y) + (y x 5) + (8 x y) + (8 x 5)
y² + 5y + 8y + 40
y² + 13y + 40

The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):

sa = 2lw + 2wh + 2lh
sa = (2 x 7 x 1) + (2 x 1 x 7) + (2 x 7 x 7)
sa = (14) + (14) + (98)
sa = 126

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.