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.

2a - 2a = 0a

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.)

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.

b + 6 = -4 - 2b
b = -4 - 2b - 6
b + 2b = -4 - 6
3b = -10
b = \( \frac{-10}{3} \)
b = -3\(\frac{1}{3}\)

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)(6ab) - (4a²)(6b)
(9 x 6)(a x a x b) - (4 x 6)(a² x b)
(54)(a¹⁺¹ x b) - (24)(a²b)
54a²b - 24a²b
30a²b

A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.