Negative discriminant how many solutions

If, however, b 2 - 4 ac is negative, then you'll have a negative inside a square root sign in the quadratic formula, meaning only imaginary solutions. Because the discriminant is negative, the quadratic equation has no real number solutions, only two imaginary ones. Michael Kelley. All rights reserved including the right of reproduction in whole or in part in any form. You can purchase this book at Amazon. See also:. Algebra: The Quadratic Formula. Trending Here are the facts and trivia that people are buzzing about.

If you haven't learnt the quadratic formula yet you'll probably learn it tomorrow in math class. Just know that, what you're looking at is whether or not b squared minus 4ac is greater than zero, less than zero or equal to zero. And it tells me how many answers I should have.

It doesn't tell me what the answers are just how many of them I should have in order to get the problem correct. Previous Unit Factoring. Next Unit Radical Expressions and Equations. Alissa Fong. Thank you for watching the video. Start Your Free Trial Learn more.

Explanation Transcript The discriminant is the term underneath the square root in the quadratic formula and tells us the number of solutions to a quadratic equation. Algebra Quadratic Equations and Functions. Well, we know how to find the solutions using the quadratic formula :.

That makes it look like we can always find solutions. However, we can't always take a square root! Sometimes you'll get a negative number under the radical. A negative under the radical means there are no real number solutions to the radical.

There are three cases:. To learn more about how to determine solutions using the x-intercepts, check out this lesson.

Using the discriminant will be really helpful when you're trying to quickly solve quadratic equation word problems later on! Let's do a little review before we investigate the discriminant. If the discriminant is less than 0, the quadratic equation has 0 real solutions. Instead of real solutions, the quadratic equation has 2 imaginary solutions. The discriminant is the part of the quadratic formula under the radical.