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).

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.

(8a)(7ab) - (6a²)(9b)
(8 x 7)(a x a x b) - (6 x 9)(a² x b)
(56)(a¹⁺¹ x b) - (54)(a²b)
56a²b - 54a²b
2a²b

A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).

The formula for circumference is circle diameter x π:

c = πd
c = 5π

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.

8y - 1 > -4 - 3y
8y > -4 - 3y + 1
8y + 3y > -4 + 1
11y > -3
y > \( \frac{-3}{11} \)
y > -\(\frac{3}{11}\)