Common SAT Algebra Mistakes (And How to Fix Them)
Lyceon Team · SAT Math · Updated October 5, 2026
Algebra is one of the four content areas in SAT Math, with 13 to 15 of the section's 44 questions. These six mistakes are easy to make and easy to fix.
Sources: College Board: the Math section overview; College Board: SAT structure
1. Answering a different question
The question asks for 2x + 1 and you stop at x = 3. The answer is 7. Fix: underline what the question asks for, and check it before you choose.
2. Sign errors when distributing
−2(x − 3) is −2x + 6, not −2x − 6. Fix: write the step out whenever a negative is involved.
3. Not checking solutions
With a variable in a denominator or under a root, a solution can fail when you plug it back in. Fix: substitute it into the original equation.
4. Misreading word problems
"3 more than twice a number" is 2x + 3, not 2(x + 3). Fix: translate one phrase at a time.
5. Flipping the slope formula
Slope is the change in y over the change in x. Fix: say "rise over run" as you write it.
6. Arithmetic slips under pressure
Fix: use the calculator. It's allowed for the whole Math section, and Desmos is built into Bluebook.
Source: College Board: calculator policy
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