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 coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.

The formula for area is πr². Radius is circle \( \frac{diameter}{2} \):

r = \( \frac{d}{2} \)
r = \( \frac{8}{2} \)
r = 4
a = πr²
a = π(4²)
a = 16π

You need to find the value of b so solve the first equation in terms of z:

-2b + z = 2
z = 2 + 2b

then substitute the result (2 - -2b) into the second equation:

-3b - 4(2 + 2b) = -9
-3b + (-4 x 2) + (-4 x 2b) = -9
-3b - 8 - 8b = -9
-3b - 8b = -9 + 8
-11b = -1
b = \( \frac{-1}{-11} \)
b = \(\frac{1}{11}\)

The volume of a cylinder is πr²h:

v = πr²h
v = π(8² x 1)
v = 64π