A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).

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.

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.

5x + 8 > \( \frac{x}{9} \)
9 x (5x + 8) > x
(9 x 5x) + (9 x 8) > x
45x + 72 > x
45x + 72 - x > 0
45x - x > -72
44x > -72
x > \( \frac{-72}{44} \)
x > -1\(\frac{7}{11}\)

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

a = l x w
a = a x b
a = 5 x 6
a = 30

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.

7a⁸ - 7a⁸ = 0a⁸