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)(4ab) + (2a²)(7b)
(8 x 4)(a x a x b) + (2 x 7)(a² x b)
(32)(a¹⁺¹ x b) + (14)(a²b)
32a²b + 14a²b
46a²b

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 - 9)(y - 8)
(y x y) + (y x -8) + (-9 x y) + (-9 x -8)
y² - 8y - 9y + 72
y² - 17y + 72

When solving an equation with two variables, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)

A triangle is a three-sided polygon. It has three interior angles that add up to 180° (a + b + c = 180°). An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite (d = b + c). The perimeter of a triangle is equal to the sum of the lengths of its three sides, the height of a triangle is equal to the length from the base to the opposite vertex (angle) and the area equals one-half triangle base x height: a = ½ base x height.

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

a = l x w
a = a x b
a = 7 x 1
a = 7