GMAT Algebra
Linear and quadratic equations, simultaneous equations, inequalities, absolute value, exponents and roots. No proofs, no calculus — and the single most punished rule is the one about inequalities and negatives.
The rules that decide questions
- Multiplying or dividing an inequality by a negative reverses it. Where the sign of a variable is unknown, you cannot divide by it at all.
- Absolute value gives two cases. |x| = 7 means x = 7 or x = −7, and the question is usually built on the one you did not write down.
- Exponent rules — same base: add the powers to multiply, subtract to divide. A negative power is a reciprocal. Anything to the power zero is one.
Factorisations worth knowing cold
| Pattern | Factors to |
|---|---|
| x² − y² | (x + y)(x − y) |
| x² + 2xy + y² | (x + y)² |
| x² − 2xy + y² | (x − y)² |
Difference of two squares is the one that turns an intimidating expression into one line, and the GMAT writes questions specifically to reward spotting it — particularly without a calculator, where the alternative is long multiplication.
Most GMAT quadratics factorise cleanly. One that does not usually means the equation was set up wrongly.
Algebra — FAQs
2 questions
Rarely. Clean factorisation is the norm and is a signal your setup is right.
Yes, and they are where the negative-sign rule costs most candidates marks.
More quantitative question types
Sources
Written from the test board's own published material and checked on 1 October 2026.