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.

You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a² - a² = 3a² but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.

The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:

b² + 4b - 5 = 0
(b - 1)(b + 5) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (b - 1) or (b + 5) must equal zero:

If (b - 1) = 0, b must equal 1
If (b + 5) = 0, b must equal -5

So the solution is that b = 1 or -5

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.

-6z + 3 = \( \frac{z}{7} \)
7 x (-6z + 3) = z
(7 x -6z) + (7 x 3) = z
-42z + 21 = z
-42z + 21 - z = 0
-42z - z = -21
-43z = -21
z = \( \frac{-21}{-43} \)
z = \(\frac{21}{43}\)

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.

8a⁹ - 6a⁹ = 2a⁹