The Digital SAT lets you use the embedded Desmos calculator on every math question. These short lessons walk through the time-savers that show up most on test day — one scenario at a time, with a real walkthrough and a quick try at the end. Adapted from DSAT 5-Day Final Review · Day 1 Desmos (Daniel Kim).
Three points → table → y₁ ~ m x₁ + b. Regression gives the slope and intercept in one move.
Flip the fraction, switch the sign. Type both lines in Desmos to verify the 90° angle visually.
Type both equations, click the intersection. Desmos hands you the (x, y) solution — no substitution, no elimination.
Type the inequality with ≤ or ≥. Desmos shades the feasible region — solid line for equality, dashed for strict.
Table → regression → click the line. Desmos labels both x- and y-intercepts so you can add them.
When the problem gives you points, not equations: two tables → two regressions → click the intersection. Same problem type, faster path when you don't have the equations in hand.
Type the equation as-is. Desmos plots both solutions as vertical lines — no case-split needed.
Three points → y₁ ~ a x₁² + b x₁ + c → all three coefficients in one move.
Same pattern, exponential form: y₁ ~ a · b^x₁ finds amplitude and base.
Vector regression [f(x₁)] ~ [g(x₁)] finds where two functions meet.
Plot the cubic, click each x-intercept. Desmos labels every root.
Plot both equations, click each intersection — Desmos labels (x, y) for each.
Real data table → linear regression → slope, intercept, and RMSE in one move.
Wrap the list in brackets, call mean(l) and median(l) — Desmos returns exact values.
Visualize spread with boxplot(l) — min, Q1, median, Q3, max at a glance.
Toggle Desmos angle mode; evaluate sin / cos / tan exactly — no unit-circle memorization.
Plot the circle, find center and radius visually. Complete the square in one move.