The Quadratic Formula – Beginning Quadratic Formula

The Quadratic Formula

For FREE access to this lesson, select your course from the categories below.

Students learn to solve quadratic equations in the form ax^2 + bx + c = 0 using the quadratic formula, which states that x = -b plus or minus the square root of b^2 – 4ac over 2a. For example, to solve the equation x^2 – 3x – 8 = 0, since a = 1, b = -3, and c = -8, the quadratic formula states that x = 3 plus or minus the square root of (-3)^2 – 4(1)(-8) over 2(1). Simplifying on the right side of the equation, x = 3 plus or minus the square root of 9 + 32 over 2, or x = 3 plus or minus the square root of 41 over 2, which is the final answer. Note that students also learn to derive the quadratic formula using completing the square in the first example problem in this lesson.
We help you determine the exact lessons you need.
We provide you thorough instruction of every step.
We`re by your side as you try problems yourself.
We test your knowledge until you`ve got it down.
We build your foundation if you`re struggling.
Login to your account
Enter your information to sign in
Lesson limit reached

The learning doesn't have to stop!

Become a MathHelp.com member today and receive unlimited access to lessons, grade reports, practice tests, and more!

Become a member

Already a member?

The learning doesn't have to stop!

Become a MathHelp.com member today and receive unlimited access to lessons, grade reports, reviews and more!

Become a member
Select your category
Test Prep
Middle and High School
College
Cancel
Which test are you preparing for?
Cancel
Select your course
Cancel
Select your course
Cancel
Select your test