The area of a triangle is equal to ½ base x height:

a = ½bh
a = ½ x 2 x 8 = \( \frac{16}{2} \) = 8

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.

(7a)(7ab) + (2a²)(5b)
(7 x 7)(a x a x b) + (2 x 5)(a² x b)
(49)(a¹⁺¹ x b) + (10)(a²b)
49a²b + 10a²b
59a²b

To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.

4a - 5a = -1a

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 + 2)
(y x y) + (y x 2) + (8 x y) + (8 x 2)
y² + 2y + 8y + 16
y² + 10y + 16

The volume of a cylinder is πr²h:

v = πr²h
v = π(8² x 2)
v = 128π