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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 |
Factoring isn’t just another algebra skill to memorize. It’s a way of understanding how polynomials are built and once you see how something is built, you can do so much more with it. You can solve equations, simplify expressions, and even figure out what a graph is going to look like just by looking at its factors.
You’ll see factoring show up in all kinds of places, like in business, coding, and even animation. But right now, our goal is simpler: to understand it deeply. In this article, we’ll explore how factoring works, step by step, and how the Symbolab Factor Polynomials Calculator can help you not just get answers but see the math more clearly.
To factor a polynomial means to write it as a product of simpler expressions. These simpler expressions, usually binomials or monomials, are the building blocks that multiply together to give you the original polynomial. If that sounds like “undoing multiplication,” you’re exactly right.
Let’s say you're organizing a school fundraiser, and you’re setting up a rectangular display area for books. You know the area needs to be $6$ square meters, and the length has to be $2$ meters longer than the width. If you let the width be $x$, then the length is $x + 2$, and the area, length times width, is $x(x + 2) = x^2 + 2x$.
Now imagine someone donates extra books, and you need to expand the area. The new model becomes $x^2 + 5x + 6$. At first glance, that expression doesn’t tell you much about the possible layout. But once you factor it into $(x + 2)(x + 3)$, suddenly, it’s clear: the new width could be $x + 2$ and the new length $x + 3$. You’ve turned an abstract polynomial into something you can actually visualize and measure.
This is what factoring does! It shows you the pieces that were multiplied together to create the expression. It takes a clean, finished product and reveals the structure behind it.
And this structure can be incredibly useful. Say you need to solve the equation $x^2 + 5x + 6 = 0$. Once it’s factored:
$(x + 2)(x + 3) = 0$
you can use the Zero Product Property, which says that if a product is zero, then one or both of the factors must be zero. That gives:
$x + 2 = 0 \quad \text{or} \quad x + 3 = 0$
so the solutions are:
$x = -2 \quad \text{or} \quad x = -3$
That’s the power of factoring. It helps us solve equations, understand graphs, and simplify expressions, and when you look closely, it often helps us connect math to real, everyday decisions.
There’s no one-size-fits-all method for factoring, and that’s a good thing. Different types of polynomials call for different strategies. The key is to learn to recognize what kind of expression you’re working with so you can choose the method that fits.
Let’s go through the most common techniques, with examples to guide your thinking.
Always start here. Before you do anything else, check whether all the terms in your polynomial have a common factor, a number, a variable, or both.
Example:
$6x^2 + 9x = 3x(2x + 3)$
We factored out $3x$ because it’s the greatest factor that both terms share. This step simplifies the expression and often makes the next steps easier.
These are expressions like $x^2 + bx + c$. You’re looking for two numbers that multiply to $c$ and add to $b$.
Example:
$x^2 + 7x + 10 = (x + 2)(x + 5)$
Because $2 \cdot 5 = 10$ and $2 + 5 = 7$.
This is often the first kind of factoring students learn, and it’s worth practicing until it becomes second nature.
When the leading coefficient (the number in front of $x^2$) isn’t 1, we need a different approach. One reliable method is called the ac method (also known as factoring by decomposition).
Example:
$2x^2 + 7x + 3$
Step 1: Multiply $a \cdot c = 2 \cdot 3 = 6$
Step 2: Find two numbers that multiply to $6$ and add to $7$.They are $6$ and $1$.
Step 3: Rewrite the middle term: $2x^2 + 6x + x + 3$
Step 4: Group and factor:
$2x(x + 3) + 1(x + 3) = (2x + 1)(x + 3)$
This method works consistently and is especially helpful when you can’t factor easily by sight.
Used when you have four terms, especially when you don’t see an obvious GCF.
Example:
$ax + ay + bx + by = a(x + y) + b(x + y) = (a + b)(x + y)$
You group the terms in pairs, factor each group, and then factor the common binomial.
This is a special pattern:
$a^2 - b^2 = (a - b)(a + b)$
You’ll spot this when two perfect squares are being subtracted.
Example:
$x^2 - 16 = (x - 4)(x + 4)$
Why? Because $x^2$ is a square, and so is $16$ (since $4^2 = 16$).
These come from squaring a binomial:
$(a + b)^2 = a^2 + 2ab + b^2$
$(a - b)^2 = a^2 - 2ab + b^2$
Example:
$x^2 + 6x + 9 = (x + 3)^2$
Since $x^2$ is a square, $9$ is a square, and $6x$ is twice the product of $x$ and $3$.
These are less common, but still important. The patterns are:
$a^3 + b^3 = (a + b)(a^2 - ab + b^2)$
$a^3 - b^3 = (a - b)(a^2 + ab + b^2)$
Example:
$x^3 - 8 = x^3 - 2^3 = (x - 2)(x^2 + 2x + 4)$
These patterns don’t come up often in early algebra, but when they do, knowing the formula is essential.
Factoring is a bit like detective work. You look for clues, how many terms are there? Do they have a GCF? Is it a trinomial or a special pattern? The more you practice spotting these clues, the more natural it becomes.
Factoring by hand is about more than following steps, it's about looking at a polynomial and thinking, “What structure does this have?” Here’s how to approach it, even if you’re not sure where to start.
Before doing anything else, ask yourself: Do all the terms share a common factor? This might be a number, a variable, or both.
Example:
$15x^3 - 10x^2 = 5x^2(3x - 2)$
Pulling out a GCF cleans up the polynomial and often makes the next steps easier.
2 terms? Try difference of squares or sum/difference of cubes.
3 terms? Look for a trinomial pattern.
4 terms? Try grouping.
For trinomials like $x^2 + bx + c$, think: What two numbers multiply to $c$ and add to $b$?
Example:
$x^2 + 9x + 14$
Find: $7$ and $2$
$(x+7)(x+2)$
For harder ones (when $a \neq 1$), use the ac method:
Example:
$3x^2 + 11x + 6$
$3 \cdot 6 = 18$, and $9 + 2 = 11$
Rewrite: $3x^2 + 9x + 2x + 6$
Group: $3x(x + 3) + 2(x + 3) = (3x + 2)(x + 3)$
After you factor, always multiply your factors to check if you get back to the original expression. If you don’t, retrace your steps. You might have chosen the wrong number pair or missed a GCF.
Try factoring by hand before you use a calculator. It strengthens your pattern recognition and number sense. This helps across all areas of math, from solving equations to graphing functions.
Factoring isn’t always smooth. Sometimes the numbers don’t cooperate, or the expression doesn’t seem to fit any pattern you’ve learned. That’s normal. The more you practice, the better you’ll get at spotting structure, and at avoiding the common slip-ups.
Here are some things to watch out for:
This is the most common oversight. If you skip the greatest common factor, your final answer might still be structurally correct, but it won’t be fully factored.
Mistake:
$6x^2 + 9x = (2x + 3)$
Better:
Factor out the GCF first:
$6x^2 + 9x = 3x(2x + 3)$
Factoring trinomials requires precision. If you guess two numbers that seem close, you might miss the mark.
Mistake:
Trying to factor $x^2 + 10x + 21$ as $(x + 4)(x + 6)$
But $4 \cdot 6 = 24$, not $21$.
Better:
$3 \cdot 7 = 21$ and $3 + 7 = 10$
So:
$(x+3)(x+7)$
Always multiply to check your answer.
Not every two-term expression is a difference of squares or a cube. Make sure it actually fits the pattern before using a shortcut.
Mistake:
Trying to factor $x^2 + 9$ as $(x + 3)(x + 3)$
This only works if it’s a perfect square trinomial.
Also, $x^2 + 9$ cannot be factored over the real numbers. It is not a difference of squares, and it is not a trinomial.
Pay attention to signs when choosing your factor pairs.
Example:
To factor $x^2 - x - 6$, you need numbers that multiply to $-6$ and add to $-1$.
That would be $-3$ and $2$.
So the correct factorization is:
$(x−3)(x+2)$
Double-check the sum and product every time.
Sometimes students stop after factoring partially , or don’t fully simplify.
Example:
$4x^3 + 8x^2 + 4x = 4x(x^2 + 2x + 1)$
But $x^2 + 2x + 1$ is a perfect square trinomial.
Fully factored:
$4x(x + 1)^2$
Factoring can feel tricky at first, especially when things don’t fall into place right away. But mistakes are part of the learning process. When something doesn't factor easily, pause. Check for a GCF. Recheck your signs. Try writing out all factor pairs and take your time.
Factoring might feel like a classroom exercise, but it plays a key role in solving real-world problems. Here's where it shows up:
Factoring turns complex expressions into something usable. Whether you're solving a design challenge or analyzing data, it helps reveal what's really going on.
Factoring by hand builds understanding, but a good tool can help you see why each step works. The Symbolab Factor Polynomials Calculator doesn’t just give answers; it walks you through the logic. Here’s how to make the most of it:
You’ve got options:
You’ll see:
On the right, you’ll see the “Chat with Symbo” option. Type in your math question, and it can explain a step or guide you through something you're not sure about.
Use Symbolab:
Factoring polynomials helps you see the structure behind expressions and equations. It’s a key to solving problems, simplifying expressions, and understanding how functions behave. Whether you’re doing it by hand or checking with Symbolab, each step builds confidence. The more you practice, the more fluent you become, and what once felt tricky starts to make sense, one factor at a time.
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