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Quadratic Equations

Quadratic Equations, a selection of answers from the Dr. Math archives.

Quadratic Equation

What is the formula for the quadratic equation?

Names of Polynomials

Why is an equation having only two roots, one of which is raised to the second power, called a quadratic equation?

What is a Quadratic Equation?

What is a quadratic equation? What is it used for? How can we use it to solve everyday problems?

Real Life Uses of Quadratic Equations

When would you solve a quadratic equation in real life?

Quadratic Formula

Could you give me some ideas for how to use the quadratic formula, and some practice problems?

Three Ways to Solve Quadratic Equations

How do I solve x^2 + 4x + 2 = 0 ?

Solving Quadratic Equations

A rectangle has an area of 80 square units. Its length is one more than three times its width. What are the dimensions of the rectangle?

Derivation of Quadratic Formula

I would like to derive the solution to ax(2) + bx + c = 0.

What Are Quadratic Functions?

What is the difference between a quadratic function and a quadratic formula?

Graphing Quadratic Polynomials

Can you give me a simple explanation of how to graph quadratic polynomials like y = x^2 - 8x + 15?

Quadratic Formulas, Equations, Parabolas, Graphing

Given 6x^2 + x - 1 = 0, how do I find the roots, the vertex, some coordinates, and from these graph it?

Factoring Quadratic Equations

Learning to Factor - Dr. Math FAQ

A sampling of answers from our archives.

From the archives:

Factoring Quadratics

How do you factor 2x^2 - 11x + 15 or 6a^2 + 7a - 5?

Factoring Quadratic Equations

Are there common points or rules I can apply in every situation?

Why FOIL?

How can I explain to the class the importance of learning FOIL?

Two Methods of Factoring Quadratics

Could you describe how to factor quadratic trinomials?

Finding a Single Pair of Factors

Factor ax^2 - bx - c.

Why Factor?

What is the practical use of factoring?

Two Values of X

Two numbers differ by 7 and the sum of their squares is 389. Find the two numbers.

The Discriminant of Quadratic Equations

Can you explain more about the discriminant, b^2 - 4ac? Why is it sometimes represented by a triangle (delta)?