How to Use the Desmos Calculator on the Digital SAT
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The Digital SAT has a Desmos graphing calculator built into the Bluebook app, and you can use it on every Math question. It is fastest for systems of equations, quadratics, intersections and checking answer choices. You may also bring your own approved calculator, but students who practise with Desmos usually save the most time.
Where Desmos saves the most time
| Question type | What to do in Desmos |
|---|---|
| Systems of equations | Type both equations and click the intersection point |
| Quadratics | Graph the function to read the vertex, roots and y-intercept |
| Number of solutions | Graph both sides and count the intersections |
| Inequalities | Graph them and test which answer choice sits in the shaded region |
| Unknown constants | Use a slider for the constant and watch the graph change |
| Statistics | Enter a list and use mean() or median() |
Desmos tips
- Type equations exactly as written. Desmos accepts y = and x = forms and most standard notation.
- Click a curve to see key points such as roots, maximums and intersections.
- Use the zoom buttons or adjust the axes when a point is off screen.
- Know when not to use it: simple arithmetic and one-step algebra are often faster by hand.
- Practise with Desmos in Bluebook practice tests, so the layout is familiar on test day.
Desmos or your own calculator?
You can bring an approved graphing or scientific calculator, and some students prefer physical buttons. Desmos is usually faster for anything involving graphs, which covers a large share of the Algebra and Advanced Math questions.