An equation is two expressions separated by an equal sign. The key to solving equations is to 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.

A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.

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 2 as well and sum (Inside, Outside) to equal -3. For this problem, those two numbers are -2 and -1. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² - 3y + 2
y² + (-2 - 1)y + (-2 x -1)
(y - 2)(y - 1)

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).

The perimeter of a triangle is the sum of the lengths of its sides:

p = x + y + z
p = 12cm + 5cm + 14cm = 31cm