ACT Math

Check your work in Desmos

October 8, 2026 · 5 min read

After you have an answer, graph the original equation or plug the value back in. A ten-second check catches the last-sentence swap. Desmos access is in Desmos on the ACT.

Confirm the thing they asked

If you solved for x, graph y = the original and y = your value, or type the substitution. Rereading the target is in reread the last sentence. Piecewise items need the right piece, in piecewise in Desmos.

Do not open a graph for arithmetic you already trust, in when not to graph.

The bottom line

Answer first, then a cheap graph or substitution. Trust but verify.

Start practicing

Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.

This article offers general ACT prep guidance. The ACT can change from year to year, including its format, scoring, policies, test dates, and fees, so always confirm the latest details on the official ACT website at act.org before you make decisions. ACT® is a registered trademark of ACT, Inc. thirty-six is not affiliated with, endorsed by, or sponsored by ACT.