VI

REFRESHER

Quadratic

Equations

An equation such as 2x^2 þ 3 x
 5 ¼0 is called aquadratic equation or a

second-degree equation. There is one variable (usuallyx) and a second-degree

term (usuallyx^2 ). There are several ways to solve quadratic equations. The

method shown here will usefactoring.If you cannot factor trinomials, you will

need to consult an algebra book to learn this skill.

A quadratic equation can be written in standard form when thex^2 term is

first, thexterm is second, and the constant term is third. Also, zero is on the

right side of the equation. For example, the quadratic equation 2xþx^2 ¼ 8

can be written in standard form asx^2 þ 2 x
 8 ¼0. In order to solve a

quadratic equation by factoring, you should follow these steps:

Step 1: Write the equation in standard form.

Step 2: Factor the left member of the equation.

Step 3: Set both factors equal to zero.

Step 4: Solve each equation.

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