Simplify Expressions Calculator

Reviewed by CalcMulti Editorial Team·Last updated: ·Algebra Hub

Simplifying an algebraic expression means rewriting it in its most compact, equivalent form by combining like terms, applying the distributive property, and using exponent rules. A simplified expression contains no parentheses that can be expanded, no like terms that can be merged, and no negative or fractional exponents that can be rewritten.

This calculator walks through simplification step by step: identifying like terms, collecting coefficients, expanding brackets using the distributive property or FOIL, and applying laws of exponents. Whether you are working with polynomials, rational expressions, or radicals, each reduction is shown explicitly so you can follow the logic and reproduce it by hand.

Simplification is not just cosmetic — it is a prerequisite for almost every further operation in algebra. A quadratic equation must be simplified before you can factor it or apply the quadratic formula. A rational expression must have its numerator and denominator simplified before you can cancel common factors. A trigonometric identity must be reduced before the pattern becomes visible. Skipping simplification creates errors that compound through every subsequent step, so building the habit of fully simplifying after each operation is one of the highest-leverage skills in algebra.

The most common simplification errors involve signs. Distributing a negative: −3(x − 4) becomes −3x + 12 (not −3x − 12). Subtracting an expression: 5x − (2x − 7) becomes 5x − 2x + 7 = 3x + 7 (not 3x − 7). These sign mistakes are the leading source of wrong answers in algebraic calculations. Always distribute the negative sign to every term inside the parentheses before combining like terms, and never drop the negative sign when moving a term across an equals sign.

Understanding the underlying rules — not just memorising the steps — makes simplification faster and more reliable. The distributive property a(b + c) = ab + ac is the engine behind both expansion and factoring. The commutative and associative properties let you reorder and regroup terms freely before collecting them. The laws of exponents (product rule, quotient rule, power rule, negative exponent rule) cover every situation involving powers. Once you can identify which rule applies to which part of an expression, simplification becomes a systematic process rather than a guess-and-check exercise.

Worked examples step by step: (1) Simplify 4x² + 3x − 2x² + 7 − 5x. Group like terms: (4x² − 2x²) + (3x − 5x) + 7 = 2x² − 2x + 7. Done — no further simplification possible. (2) Simplify 2(3x − 4) − 3(x + 2). Distribute: 6x − 8 − 3x − 6. Combine: (6x − 3x) + (−8 − 6) = 3x − 14. (3) Expand and simplify (2x + 3)(x − 5). FOIL: 2x·x + 2x·(−5) + 3·x + 3·(−5) = 2x² − 10x + 3x − 15 = 2x² − 7x − 15. (4) Simplify x³·x⁻² = x^(3+(−2)) = x¹ = x. These four operations — combining like terms, distributing, FOIL, and exponent rules — cover the vast majority of simplification tasks encountered in algebra courses.

Simplifying rational expressions requires an extra step: factor numerator and denominator before cancelling. Example: simplify (x² − 9)/(x² + 5x + 6). Factor: (x − 3)(x + 3) / (x + 2)(x + 3). Cancel (x + 3) from both: (x − 3)/(x + 2), restricted to x ≠ −3 (the cancelled factor creates a restriction). A common error is cancelling terms instead of factors: (x² + 5)/(x²) cannot be simplified to 1 + 5 — you can only cancel factors that multiply the entire numerator and denominator. Similarly, (x + 4)/(x + 7) cannot be simplified because x is a term (added), not a factor (multiplied).

The laws of exponents handle every power situation systematically. Product rule: xᵃ · xᵇ = x^(a+b). Quotient rule: xᵃ / xᵇ = x^(a−b). Power rule: (xᵃ)ᵇ = x^(ab). Zero exponent: x⁰ = 1 (for x ≠ 0). Negative exponent: x⁻ⁿ = 1/xⁿ. Fractional exponent: x^(m/n) = (x^m)^(1/n) = ⁿ√(xᵐ). Worked example: simplify (2x³y²)² / (4x⁵y). Apply power rule: 4x⁶y⁴ / 4x⁵y. Divide coefficients: 1. Apply quotient rule for x: x^(6−5) = x. For y: y^(4−1) = y³. Result: xy³.

Formula

Like terms: axⁿ + bxⁿ = (a+b)xⁿ | Distributive: a(b+c) = ab+ac | FOIL: (a+b)(c+d) = ac+ad+bc+bd

like terms
terms with the same variable(s) raised to the same power(s)
distributive property
a(b+c) = ab+ac — multiply each term inside the bracket by the factor outside
FOIL
First, Outer, Inner, Last — method for expanding two binomials (a+b)(c+d)

Simplify Algebraic Expressions

Choose a simplification method and enter values.

( ax + b )( cx + d )

Common Simplification Mistakes

✕ Wrong: −3(x − 4) = −3x − 12

✓ Right: −3(x − 4) = −3x + 12

Distributing a negative flips every sign inside the brackets. −3 × (−4) = +12.

✕ Wrong: 5x − (2x − 7) = 3x − 7

✓ Right: 5x − (2x − 7) = 5x − 2x + 7 = 3x + 7

Subtracting an expression means distributing −1 to every term inside. −(2x − 7) = −2x + 7.

✕ Wrong: (x + 3)² = x² + 9

✓ Right: (x + 3)² = x² + 6x + 9

You must FOIL (or use the perfect square formula a² + 2ab + b²). The middle term 2(x)(3) = 6x cannot be dropped.

✕ Wrong: (x + 4) / (x + 7) → cancel x → 4/7

✓ Right: (x + 4) / (x + 7) — cannot be simplified

You can only cancel factors (multiplied), not terms (added). x is a term here, not a factor of the whole expression.

✕ Wrong: x³ + x² = x⁵

✓ Right: x³ + x² cannot be combined further (different powers)

Exponent rules apply to multiplication (x³ × x² = x⁵), not addition. Adding powers with different exponents requires combining like terms — these are not like terms.

Fully Simplified Checklist

An expression is fully simplified when all of the following are true:

  • No parentheses remain that can be expanded (all brackets distributed)
  • No like terms remain (all terms with the same variable and exponent are combined)
  • No negative exponents (rewrite x⁻ⁿ as 1/xⁿ)
  • No fractional exponents that can be written as radicals (or vice versa, per context)
  • No common factors in numerator and denominator (for rational expressions)
  • Coefficients are in lowest terms (e.g., 6x/4 simplified to 3x/2)
  • Leading term has a positive coefficient (optional but standard for polynomials)

Simplification Rules

RuleFormulaExample
Combine like termsaxⁿ + bxⁿ = (a+b)xⁿ3x² − 7x² = −4x²
Distributive propertya(b+c) = ab+ac3(2x+5) = 6x+15
FOIL(a+b)(c+d) = ac+ad+bc+bd(x+2)(x−3) = x²−x−6
Difference of squaresa²−b² = (a+b)(a−b)x²−9 = (x+3)(x−3)
Perfect square(a+b)² = a²+2ab+b²(x+3)² = x²+6x+9
Negative exponentx⁻ⁿ = 1/xⁿx⁻² = 1/x²
Product of powersxᵃ·xᵇ = x^(a+b)x³·x² = x⁵
Quotient of powersxᵃ/xᵇ = x^(a−b)x⁵/x² = x³
Power of power(xᵃ)ᵇ = x^(ab)(x²)³ = x⁶

Disclaimer

This calculator is for educational purposes only and does not constitute professional advice. Results are based on standard mathematical formulas. Always verify critical calculations with a qualified professional before making important decisions.

Frequently Asked Questions