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▭\:\longdivision{▭} | \times \twostack{▭}{▭} | + \twostack{▭}{▭} | - \twostack{▭}{▭} | \left( | \right) | \times | \square\frac{\square}{\square} |
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- \twostack{▭}{▭} | \lt | 7 | 8 | 9 | \div | AC |
+ \twostack{▭}{▭} | \gt | 4 | 5 | 6 | \times | \square\frac{\square}{\square} |
\times \twostack{▭}{▭} | \left( | 1 | 2 | 3 | - | x |
▭\:\longdivision{▭} | \right) | . | 0 | = | + | y |
The first time you see a radical equation, something like $√(x + 3) = 7$ — it can feel as if math is suddenly speaking another language. Radicals (that’s the proper name for those root symbols, by the way) have this strange ability to make even the calmest student raise an eyebrow. What’s that root doing? Why is the variable under it? And how on earth are you supposed to get $x$ alone when it’s tucked inside a square root? If you’ve ever had those questions, you’re not alone. Radical equations look trickier than they are. At their core, they’re just equations, with one twist: the variable you’re solving for lives inside a root. That changes how you approach them, but it doesn’t mean they’re unsolvable.
In this guide, we’re going to break radical equations down into bite-sized steps. We'll walk through examples together, troubleshoot the common mistakes (hello, extraneous solutions), and show you how to use the Symbolab Radical Equation Calculator to check your work or explore problems that get too tangled to untie by hand.
A radical equation is an equation that includes a variable inside a radical — usually a square root $(√)$, but sometimes a cube root $(∛)$ or other roots too. The “radical” part just refers to the root symbol, which tells you to take the square root, cube root, or another type of root of a number or expression.
In plain terms: if you see an equation where x is sitting inside a square root or cube root, you’re looking at a radical equation.
Here are a couple of examples:
$√(x + 3) = 7$
$∛(32x - 1) = 4$
In the first example, $x$ is part of a square root expression. In the second, it’s under a cube root. Your goal, just like with any equation, is to solve for $x$ — to figure out what number makes the equation true. But here’s what makes radical equations a little different: you can't just “move” the variable around like you would in a simple linear equation. First, you need to get rid of the root, and to do that, you do the opposite of taking a square root or cube root. You raise both sides to a power, like squaring or cubing.
This extra step is what gives radical equations their unique flavor. It's also where many students get tripped up, especially when squaring both sides creates extraneous solutions (we’ll get to those soon). But don’t worry. Once you understand the method, solving them can actually feel kind of empowering.
A Real-Life Example: Budgeting with a Twist
Let’s imagine a more down-to-earth scenario. Say you’re shopping for a birthday gift, and you walk into one of those trendy gift shops that sells mystery boxes — you know, those where the value of the stuff inside is a surprise, but the price is based on some funky formula.
The shopkeeper tells you, “Each box costs the square root of the value of the items inside, plus two dollars for wrapping and packaging.”
You’ve got a budget of USD $6$. Your brain immediately thinks: Okay, how much value can I actually get inside the box if I’m only spending six bucks?
Here’s what the shopkeeper’s pricing rule looks like in equation form: $Price = √(value) + 2$
Since you only have USD $6 to spend, you set the price equal to 6:
$6 = √(x) + 2$
Where x is the value of the items in the box. Now, to figure out what $x$ is, in other words, how much value you’re getting inside the box, you need to solve this equation.
Start by subtracting $2$ from both sides:
$6 - 2 = √(x)$
$4 = √(x)$
Now, to get rid of the square root, you do the opposite — square both sides:
$(4)² = x$
$16 = x$
So, the mystery box you're buying for USD $6$ has USD $16$ worth of goodies inside.
That’s a radical equation in action, a real scenario where solving for a variable inside a square root helped you decide. And whether it’s budgeting for gifts, figuring out how long a task will take, or working with formulas in science, radical equations pop up more often than you’d expect.
Solving a radical equation means finding the value of the variable that makes the equation true, even when that variable is hidden inside a square root or cube root. The key is to isolate the radical first, then get rid of it by doing the opposite operation. For square roots, that means squaring both sides. For cube roots, you’d cube both sides.
Let’s walk through a basic example together, one step at a time.
Example Problem:
$√(x +2) = 5$
Step 1: Isolate the radical expression
You want the radical all by itself on one side of the equation. In this case, it already is:
$√(x +2) = 5$
If it weren’t, you'd first move any extra numbers away from it using addition, subtraction, multiplication, or division.
Step 2: Eliminate the radical
To cancel out the square root, you need to do the inverse operation. In this case, square both sides of the equation:
$ (x + 2)^2 = 5^2$
$ x + 2 = 25 $
When you square a square root, they cancel each other out, leaving just the expression underneath.
Step 3: Solve the resulting equation
Now that the radical is gone, you’re left with a regular linear equation:
$x + 2 = 25$
Subtract $2$ from both sides:
$x = 25 - 2$
$ x = 23$
Step 4: Check your solution
This is a critical step. Any time you deal with radicals, especially when you square both sides, you might accidentally introduce what’s called an extraneous solution. That’s a solution that looks right algebraically but doesn’t actually work in the original equation.
Let’s plug $x = 23$ back into the original equation:
$√(23 + 2) = √25 = 5$
Since both sides match, $x = 23$ is a valid solution.
Some radical equations are clean and simple, one root, a few steps, and you’re done. But others show up looking like they’ve got baggage: multiple radicals, nested expressions, or extra terms that don’t quite play nice. And while they might seem overwhelming at first glance, the core strategy remains the same: isolate, eliminate, solve, and check. The difference is, you may need to go through the process more than once.
Let’s take a look at a more layered example, and talk through it gently, the way we wish all confusing things in life were explained.
Example Problem:
$√(x + 2) + √(x - 1) = 5$
This one’s a little messier. Two radicals on the same side. But that doesn’t mean it’s impossible, just that we have to take it one step at a time, with a little more care.
Step 1: Isolate one of the radicals
Start by getting one of the radicals on its own. It doesn’t matter which one — pick whichever feels more comfortable.
Let’s isolate $√(x + 2)$:
$√(x + 2) = 5 - √(x - 1)$
That’s a good place to begin. We’ll work on clearing out the left-hand radical first.
Step 2: Eliminate the isolated radical
To eliminate the square root, we square both sides. This is a delicate moment — it works, but it can also introduce errors if we’re not careful.
$(√(x + 2))² = (5 - √(x - 1))²$
$ x + 2 = 25 - 10√(x - 1) + (x - 1)$
Now simplify:
$x + 2 = x + 24 - 10√(x - 1)$
Next, subtract $x$ from both sides:
$2 = 24 - 10√(x - 1)$
Then subtract $24$:
$-22 = -10√(x - 1)$
Divide both sides by $-10$:
$ √(x - 1) = \frac{11}{5}$
Almost there, just one radical left.
Step 3: Solve for the remaining radical
Now that we’ve isolated the second root, we square both sides again:
$(√(x - 1))² = \left(\frac{11}{5}\right)^2$
$ x - 1 = \frac{121}{25}$
Add 1 to both sides (or $\frac{25}{25}$, to be exact):
$x = \frac{121}{25} + \frac{25}{25} = \frac{146}{25}$
This is our possible solution, but we’re not done until we’re sure it actually works.
Step 4: Check your solution
Let’s plug $x = \frac{146}{25}$ back into the original equation to make sure it holds up:
$√(\frac{146}{25} + 2) + √(\frac{146}{25} - 1)$
$= \sqrt{\frac{196}{25}} + \sqrt{\frac{121}{25}}$
$ = \frac{14}{5} + \frac{11}{5} = \frac{25}{5} = 5$
Both sides match. Which means the solution is valid.
Final Answer:
$x = \frac{146}{25}$
These more complex radical equations can feel like puzzles with too many pieces. But the trick is to keep your process steady, one radical at a time, one line at a time. Don’t let the layers throw you. Just keep clearing away until what’s underneath makes sense.
And if you’re ever unsure? Go back and check. Your answer will either stand up or quietly fall apart — and both are good outcomes, because now you know what to fix.
A Good Rule of Thumb:
Whenever you square both sides of an equation, whether once or twice, always assume that you might have introduced an extraneous solution. Assume nothing is guaranteed until you check.
Even better: build it into your process. Like brushing your teeth or reading the last message twice before sending it, make checking automatic. It’ll save you points, time, and more than a few facepalms.
Here’s the thing about radical equations: they look simple, all those gentle curves and neat little square roots — but they’re sneaky. They’re the kind of problems that can go sideways fast if you rush, skip steps, or assume the rules are the same as other equations.
So let’s slow down and talk about the most common mistakes students make, and how to avoid them. These are the places we all tend to stumble. The good news? Once you know what to look for, it’s easier to stay steady.
We just talked about this, but it’s worth repeating. Squaring both sides of an equation can create answers that don’t actually work in the original problem. You must check your solution by plugging it back in. It’s not optional. It’s part of solving.
What to do instead: Always, always go back to the original equation, the one with the radical. Substitute your answer and make sure both sides really are equal.
Sometimes, students try to square both sides before fully isolating the radical. But if you don’t isolate the radical first, squaring will create extra cross terms that make the problem messier, and way harder to solve.
What to do instead: Be patient. Move all constants or extra terms away from the radical first. Only square once the radical is truly on its own side of the equation.
Mistake #3: Losing Track of Parentheses
This one’s sneaky. When you write out your steps, especially during squaring, forgetting to use parentheses can lead to wrong calculations. For example:
Wrong: $√x + 2² = x + 4$
Right: $(√x + 2)² = x + 4√x + 4$
Big difference, right?
What to do instead: Use parentheses generously. Treat them like seat belts for your math, they keep everything where it’s supposed to be during the ride.
Mistake #4: Assuming All Radicals Have One Solution
Here’s something we don’t always talk about: not every radical equation has a solution. Sometimes you do all the right steps and still end up with an answer that doesn’t work. Or no solution at all. That’s not a failure, it’s just how math works sometimes.
What to do instead: Be open to the possibility that an equation has no real solution. If checking your answer leads to a contradiction, trust that result. It’s valid.
Mistake #5: Mixing Up Square Roots and Absolute Values This one’s a little more subtle. When you square a square root, you get the absolute value of the expression, not just the expression itself. So $√(x²) = |x|$, not $x$. That distinction matters, especially in more advanced problems.
What to do instead: Watch for square roots of squared variables. Remember that squaring and square-rooting don’t always cancel out perfectly when variables are involved.
It’s easy to get caught up in speed, to want to solve quickly, especially when the steps feel repetitive. But radical equations reward attention to detail more than anything else. Slow down. Write everything out. Talk yourself through each move like you're teaching it to someone else.
Physics: Calculating how long it takes something to fall (free-fall motion uses square roots).
Engineering: Figuring out stress or load capacity often involves square roots of force or area.
Architecture: Designing ramps or support beams requires solving for lengths using the Pythagorean theorem, a classic radical equation.
Finance: Some compound interest formulas and risk models involve roots, especially when reversing exponential growth.
Medicine: Drug dosage based on body surface area often uses square root formulas.
Computer Graphics: Calculating distances between points in 2D or 3D space involves square roots, essential in video game design and animation.
Solving radical equations by hand is important, no question. It teaches you how the math works, what each step means, and where to be careful. But sometimes, especially when you're learning a new concept or reviewing late at night with tired eyes and half a notebook already filled, you just want a little reassurance.
That’s where the Symbolab Radical Equation Calculator comes in. It’s not just about getting the right answer, it’s about seeing how to get there. Slowly. Clearly. One step at a time. Here’s how to use it.
Step 1: Open the Calculator
Go to the Symbolab Radical Equation Calculator. You can find it by typing “Symbolab radical equation calculator” into your preferred search engine, or by heading straight to the Symbolab site. If you’re doing homework online, you can also use the Symbolab Chrome Extension, just click the icon and screenshot your equation. No tab-switching, no fuss.
Step 2: Enter Your Equation
Type the equation into the input box. You can use standard math symbols — like sqrt() for square roots, or just write it in words.
For example:
If you’re solving: $ √(3x + 1) - 2 = 4$
You can type: $sqrt(3x + 1) - 2 = 4$ or even just write it out in words: square root of $3x$ plus $1$ minus $2$ equals $4$
There’s also an on-screen math keypad, which is especially useful on mobile. Tap in the square root symbol, exponents, parentheses, everything you need is right there.
Step 3: Click “Go” Once the equation’s entered, hit the “Go” button.
The calculator gets to work, not just solving, but showing you the process, the logic, the algebra behind each move. Like a digital tutor who doesn’t just hand you the answer and walk away.
Step 4: Review the Step-by-Step Solution
This is where Symbolab shines. You don’t just get “$x = something.$” You get the full play-by-play.
For our example:
$ √(3x + 1) - 2 = 4$
Symbolab will walk you through:
Isolating the square root:$ √(3x + 1) = 6$
Squaring both sides: $3x + 1 = 36$
Solving for $x$: $x = \frac{35}{3}$
You can even toggle “One step at a time” if you want to move slowly or need a pause between steps to take notes or breathe.
Step 5: Verify the Solution
Remember when we talked about extraneous solutions? Symbolab gets that too. After solving, it double-checks the solution by plugging it back into the original equation.
So if it says $x = \frac{35}{3}$, it’ll show you that plugging it back in actually works or not. And if not? It’ll explain why.
Step 6: Explore the Graph
Underneath the steps, you’ll find a graph that brings the equation to life visually.
For example, the calculator might plot:
$ √(3x + 1) - 2 - 4$
This lets you see where the expression equals zero, where the left side meets the right side, and connects all that algebra to a curve crossing the x-axis. If you’re a visual learner, this step makes a huge difference.
Bonus: Save or Share Your Work
You can bookmark the solution or, if you’re logged into your account, save it to your Symbolab Notebook. There’s also a built-in chat assistant, Symbo, for when you hit a wall or want clarification on a particular step.
Why Use the Calculator?
It builds confidence by walking you through every step
It helps you check your homework, not just the answers, but the process
It catches mistakes before they become habits
It shows the connection between algebra and graphs
It’s accessible, desktop, mobile, even as a Chrome extension
Whether you’re learning, practicing, or reviewing, the Symbolab Radical Equation Calculator turns math from something you struggle through into something you can explore, clearly, visually, and with a little less stress. Solving radical equations isn’t just about finding $x$, it’s about learning how to think clearly through complexity. From square roots to real-world scenarios, you now have the tools to break these problems down step by step. And with resources like the Symbolab calculator, you’re never working alone. Stay curious, check your work, and trust the process. You’ve got this.
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