Skip to main content

Real Solutions

Real solutions are the real-number answers to an equation, usually a quadratic, instead of imaginary or complex answers. In Elementary Algebra, you check whether a quadratic has real solutions by solving it and looking at the discriminant or square root property.

Last updated July 2026•Fiveable Content Team

What are the Real Solutions?

Real solutions are the answers to an equation that come out as real numbers, like 3, -2, or 1/4. In Elementary Algebra, the term usually shows up when you solve a quadratic equation and want to know whether the answers stay on the real number line or turn into imaginary numbers.

For quadratics, real solutions can be found in a few ways. If the equation factors nicely, you can solve it by setting each factor equal to zero. If it has a square term isolated, you can use the square root property. If neither of those is convenient, the quadratic formula gives every solution directly.

The big idea is that not every quadratic has real solutions. A quadratic can have two real solutions, one real solution, or no real solutions at all. That depends on the discriminant, which is the part under the square root in the quadratic formula: b^2 - 4ac.

If the discriminant is positive, the square root is a real number, so you get two real solutions. If it is zero, the square root is 0, so both answers collapse into one real solution. If it is negative, you cannot take the square root as a real number, so the equation has no real solutions and you move into imaginary or complex solutions instead.

Here is a quick example. For x^2 - 5x + 6 = 0, factoring gives (x - 2)(x - 3) = 0, so the real solutions are x = 2 and x = 3. For x^2 + 4 = 0, there are no real solutions because x^2 would have to equal -4, and no real number squared gives a negative result.

A common mistake is thinking every equation has real solutions just because it can be written nicely. In this unit, you always want to check the form of the equation and notice whether the final square root step stays positive, zero, or negative.

Why the Real Solutions matter in Elementary Algebra

Real solutions are the answers you expect to land on first in Elementary Algebra, especially when you are solving quadratic equations. They tell you whether a graph crosses the x-axis, whether a word problem has real-world values, and whether your algebra steps ended in a real-number answer or pushed you into imaginary numbers.

That makes the term useful in more than one way. When a quadratic has two real solutions, those answers usually match the x-intercepts of the graph. When it has one real solution, that means the parabola just touches the x-axis at one point. When it has no real solutions, the graph never meets the x-axis, which is a clue that the equation cannot be solved with real numbers only.

Real solutions also help you check your work. If you use the quadratic formula and get a negative number under the square root, that tells you right away that the equation has no real solutions. If you use the square root property, you can tell whether the right side is allowed to produce a real answer before you even finish simplifying.

This term matters because Elementary Algebra is full of equations that look solvable until the last step. Knowing what counts as a real solution keeps you from forcing an answer that does not belong and helps you describe the result correctly in homework, quizzes, and class discussions.

Keep studying Elementary Algebra Unit 10

Official unit cheatsheet

open one-pager

How the Real Solutions connect across the course

Quadratic Equation

Real solutions come up most often with quadratic equations, because quadratics can have two, one, or no real answers depending on the expression. When you solve a quadratic, you are often checking whether its roots are real numbers or whether the equation only leads to imaginary values.

Imaginary Solutions

Imaginary solutions show up when the equation would require the square root of a negative number. If a quadratic has no real solutions, the answers usually move into imaginary numbers instead, so this is the next idea to compare with real solutions.

Complex Solutions

Complex solutions include real and imaginary parts together. A quadratic with no real solutions still has complex solutions, which is why a problem can be “unsolved” over the real numbers but still have answers in the complex number system.

Imaginary Unit

The imaginary unit, i, is what lets you write square roots of negative numbers in algebra. If a quadratic does not have real solutions, the imaginary unit is the tool you use to express the answers instead of stopping at a negative square root.

Are the Real Solutions on the Elementary Algebra exam?

A problem set question might ask you to solve a quadratic and then name whether the solutions are real. Your job is to finish the algebra, then interpret the result correctly. If the discriminant is positive, write two real solutions. If it is zero, give one real solution. If the square root turns negative, say there are no real solutions instead of guessing decimals or leaving the answer incomplete.

You may also see short answer items where you need to decide, from the equation alone, whether real solutions exist. In that case, you use the discriminant or the structure of the equation to make the call before solving. A graphing task can ask the same thing in visual form: if the parabola crosses the x-axis, the x-intercepts are real solutions.

The Real Solutions vs Imaginary Solutions

Real solutions and imaginary solutions are opposites in the sense that real solutions stay on the real number line, while imaginary solutions involve the square root of a negative number. A quadratic can have two real solutions, one real solution, or no real solutions, and the last case often leads to imaginary answers instead.

Key things to remember about the Real Solutions

  • Real solutions are equation answers that are real numbers, not imaginary or complex numbers.

  • In Elementary Algebra, the term usually appears when you solve quadratic equations and check what kind of answers they produce.

  • A positive discriminant means two real solutions, a zero discriminant means one real solution, and a negative discriminant means no real solutions.

  • The square root property and the quadratic formula are the main tools you use to find out whether a quadratic has real solutions.

  • If you get a negative number under a square root, the equation does not have real solutions, even if it still has complex ones.

Frequently asked questions about the Real Solutions

What is real solutions in Elementary Algebra?

Real solutions are the answers to an equation that are real numbers, like integers, fractions, or decimals. In Elementary Algebra, this usually comes up with quadratic equations, where you check whether the solutions stay real or turn imaginary.

How do you know if a quadratic has real solutions?

Look at the discriminant, b^2 - 4ac. If it is positive, the quadratic has two real solutions. If it is zero, it has one real solution. If it is negative, it has no real solutions.

Is a real solution the same as a rational solution?

No. A real solution just means the answer is a real number. It can be rational, like 2 or 3/4, or irrational, like sqrt(5). Rational is narrower than real.

What happens if a quadratic has no real solutions?

That means the answers are not real numbers, usually because the equation would require the square root of a negative number. In that case, you describe the solutions as imaginary or complex instead of forcing a real answer.