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

a = l x w
a = a x b
a = 3 x 5
a = 15

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 6 x 6) + (2 x 6 x 8) + (2 x 6 x 8)
sa = (72) + (96) + (96)
sa = 264

For parallel lines with a transversal, the following relationships apply:

• angles in the same position on different parallel lines equal each other (a° = w°, b° = x°, c° = z°, d° = y°)
• alternate interior angles are equal (a° = z°, b° = y°, c° = w°, d° = x°)
• all acute angles (a° = c° = w° = z°) and all obtuse angles (b° = d° = x° = y°) equal each other
• same-side interior angles are supplementary and add up to 180° (e.g. a° + d° = 180°, d° + c° = 180°)

Applying these relationships starting with a° = 22, the value of z° is 22.

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)(4ab) - (4a²)(6b)
(3 x 4)(a x a x b) - (4 x 6)(a² x b)
(12)(a¹⁺¹ x b) - (24)(a²b)
12a²b - 24a²b
-12a²b

To factor a quadratic expression, apply the FOIL (First, Outside, Inside, Last) method in reverse.