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.

(5a)(2ab) - (8a²)(5b)
(5 x 2)(a x a x b) - (8 x 5)(a² x b)
(10)(a¹⁺¹ x b) - (40)(a²b)
10a²b - 40a²b
-30a²b

A trapezoid is a quadrilateral with one set of parallel sides.

To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the > sign and the answer on the other.

8x + 8 > 3 - 4x
8x > 3 - 4x - 8
8x + 4x > 3 - 8
12x > -5
x > \( \frac{-5}{12} \)
x > -\(\frac{5}{12}\)

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 8 x 7) + (2 x 7 x 4) + (2 x 8 x 4)
sa = (112) + (56) + (64)
sa = 232

To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

9z - 2 = 7 + 4z
9z = 7 + 4z + 2
9z - 4z = 7 + 2
5z = 9
z = \( \frac{9}{5} \)
z = 1\(\frac{4}{5}\)