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.

9z - 6 < 3 + 8z
9z < 3 + 8z + 6
9z - 8z < 3 + 6
z < 9

To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce -27 as well and sum (Inside, Outside) to equal 6. For this problem, those two numbers are -3 and 9. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 6y - 27
y² + (-3 + 9)y + (-3 x 9)
(y - 3)(y + 9)

The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -1) and (2, -5) so the slope becomes:

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.

5a⁷ + 7a⁷ = 12a⁷

A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s²).