Quadratics and polynomials

This course is a part of Algebra basics, a 8-course Topic series from Khan Academy.

We'll now progress beyond the world of purely linear expressions and equations and enter the world of quadratics (and more generally polynomials). Learn to factor expressions that have powers of 2 in them and solve quadratic equations. We'll also learn to manipulate more general polynomial expressions.

This course contains 9 segments:

Adding & subtracting polynomials

Learn how to add and subtract polynomial expressions with one variable.

Multiplying binomials

Learn how to multiply monomials and binomials.

Special products of binomials

Learn about the special types of products of binomials: perfect squares and the difference of two squares. These will be very helpful once you tackle more advanced expressions in Algebra.

Factoring polynomials by taking common factors

Learn how to take a common monomial factor out of a polynomial expression. For example, write 2x³+6x²+8x as (2x)(x²+3x+4).

Factoring quadratics 1

Learn how to factor quadratic expressions with a leading coefficient of 1. For example, factor x²+3x+2 as (x+1)(x+2).

Factoring quadratics 2

Learn how to factor quadratic expressions with a leading coefficient other than 1. For example, factor 2x²+7x+3 as (2x+1)(x+3).

Factoring quadratics: Difference of squares

Learn how to factor quadratics that have the "difference of squares" form. For example, write x²-16 as (x+4)(x-4). Learn how to identify this form in more elaborate expressions. For example, write 4x²-49 as (2x+7)(2x-7).

Factoring quadratics: Perfect squares

Learn how to factor quadratics that have the "perfect square" form. For example, write x²+6x+9 as (x+3)². Learn how to identify these forms in more elaborate expressions. For example, write 4x²+28x+49 as (2x+7)².

Solving quadratic equations by factoring

In this tutorial, you'll learn some pretty elaborate ways of solving quadratic equations, by harnessing the mighty strength of algebra.