To graph a piece of a function in Desmos, type the equation, then restrict x with curly braces, like y = 2x {0 ≤ x ≤ 5}. Piecewise questions and limited domains both need this. Desmos access is in Desmos on the ACT.
Cut the graph to the interval
The ACT often asks for a function only on 0 to 10, or for two rules glued at a point. Restrict each piece, then read intercepts or intersections on that window. Piecewise algebra is in piecewise functions. Domain and range as a topic are in domain and range.
Intersections on the restricted graphs are still a click, in finding intersections.
The bottom line
Type the rule. Brace the x-values the question actually uses.
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.