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Algebraic Expression Simplifier

Combine Like Terms · Expand · Multiply · Factor

Simplify polynomial expressions step by step. Supports combining like terms, distributing brackets, FOIL multiplication, and quadratic factoring with multi-variable polynomials.

Quick Examples

Use ^ for powers (x^2), * for multiplication (2*x or just 2x). Variables: x, y, z.

What Is Algebraic Expression Simplification?

Simplifying an algebraic expression means rewriting it in its most compact equivalent form without changing its value. The main techniques are combining like terms, expanding parentheses using the distributive property, multiplying polynomials, and factoring to reverse expansion. Mastering these skills is the foundation of all algebra.

Combining Like Terms

Like terms are monomials that share exactly the same variable factors at the same powers. For example, 5x² and -3x² are like terms because both are multiples of x², so their coefficients can be added: 5x² + (-3x²) = 2x². Unlike terms — such as 4x and 4x² — cannot be combined because their variable parts differ.

The step-by-step process is: (1) list every term, (2) group terms by their variable signature, (3) sum the coefficients within each group, and (4) write the result in descending degree order.

Example

3x² + 2x − x² + 5x − 3

Group x² terms: 3x² − x² = 2x²

Group x terms: 2x + 5x = 7x

Constant: −3

Result: 2x² + 7x − 3

The Distributive Property and Expanding Brackets

The distributive property states a(b + c) = ab + ac. When two polynomial factors are adjacent — like (2x + 3)(x − 4) — every term of the first factor must be multiplied by every term of the second. For two binomials, this is commonly described by the FOIL method: First, Outer, Inner, Last.

FOIL Example: (2x+3)(x−4)

PairProduct
First: 2x × x2x²
Outer: 2x × (−4)−8x
Inner: 3 × x3x
Last: 3 × (−4)−12

Combine like terms: 2x² + (−8x + 3x) − 12 = 2x² − 5x − 12

Polynomial Degree and Standard Form

The degree of a monomial is the sum of its variable exponents: 3x²y has degree 3. The degree of a polynomial is the degree of its highest-degree term. Standard form lists terms in descending degree order: 4x³ − 2x² + x − 7. This makes it easy to identify the leading coefficient (4), degree (3), and constant term (−7).

Factoring Quadratics

Factoring reverses expansion. For a quadratic ax² + bx + c, the discriminant D = b² − 4ac determines the nature of roots:

  • D > 0: two distinct real roots r₁, r₂ → a(x − r₁)(x − r₂)
  • D = 0: one repeated real root r → a(x − r)²
  • D < 0: no real factors (roots are complex conjugates)

For example, x² + 5x + 6: D = 25 − 24 = 1, roots = (−5 ± 1)/2 = −2 and −3, so the factored form is (x + 2)(x + 3).

Real-World Applications

  • Physics: Kinematic equations use polynomial expressions for position, velocity, and acceleration.
  • Engineering: Beam deflection, stress formulas, and control systems rely on polynomial algebra.
  • Finance: Compound interest and present value formulas expand into polynomial series.
  • Computer Graphics: Bezier curves and surface patches are defined by polynomial equations.
  • Data Science: Polynomial regression models fit data using multi-degree polynomials.

Frequently Asked Questions

What are like terms in algebra?
Like terms are terms that share the same variable(s) at the same power(s). 3x² and −7x² are like terms (combine to −4x²), while 3x and 3x² are not (different degrees). Only like terms can be added or subtracted — you simply add their numerical coefficients.
How do you combine like terms step by step?
(1) List all terms. (2) Group terms by variable signature (same variable, same exponent). (3) Sum coefficients within each group. (4) Write the result in descending degree order. For 3x² + 2x − x² + 5x − 3: group x² terms → 2x², group x terms → 7x, constant → −3, giving 2x² + 7x − 3.
What is the FOIL method for multiplying polynomials?
FOIL (First, Outer, Inner, Last) is a mnemonic for multiplying two binomials: (a+b)(c+d) = ac + ad + bc + bd. For (2x+3)(x−4): First = 2x², Outer = −8x, Inner = 3x, Last = −12. Combining like terms gives 2x² − 5x − 12. For polynomials with more than two terms each, the same principle applies — every term of A multiplies every term of B.
How do you factor a quadratic expression ax²+bx+c?
Compute discriminant D = b²−4ac. If D ≥ 0, roots are r = (−b ± √D)/(2a) and the factored form is a(x−r₁)(x−r₂). If D = 0, it's a perfect square: a(x−r)². If D < 0, no real factors exist. For x²+5x+6: D = 1, roots −2 and −3 → (x+2)(x+3).
What is the distributive property in algebra?
The distributive property states a(b+c) = ab + ac. It allows multiplying a factor by every term inside parentheses. For (2x+3)(x−4), distribute 2x over (x−4) to get 2x² − 8x, then distribute 3 over (x−4) to get 3x − 12. Combine to get 2x² − 5x − 12.
Can the simplifier handle multi-variable expressions?
Yes. Expressions with x, y, and z are supported. Like-term grouping uses the full variable signature, so 3xy and 5xy combine (both x¹y¹), while 3xy and 3x²y do not. Multi-variable polynomial addition, subtraction, and multiplication are all fully supported with step-by-step output.
What is the degree of a polynomial?
The degree of a polynomial is the highest total exponent among all its terms. For 4x³ − 2x + 7, the degree is 3. For a multi-variable term like 3x²y³, its degree is 5 (2+3). Classifications: degree 0 = constant, 1 = linear, 2 = quadratic, 3 = cubic, 4 = quartic, 5 = quintic.