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.

(3a)(8ab) + (9a²)(3b)
(3 x 8)(a x a x b) + (9 x 3)(a² x b)
(24)(a¹⁺¹ x b) + (27)(a²b)
24a²b + 27a²b
51a²b

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 + 6)(y + 3)
(y x y) + (y x 3) + (6 x y) + (6 x 3)
y² + 3y + 6y + 18
y² + 9y + 18

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.

9a x 3b = (9 x 3) (a x b) = 27ab

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.

The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)² : a = π r².