Digital SAT Algebra Clinic Cheatsheet
Digital SAT Algebra Cheatsheet
Published
Pocket card for forms and flips — not a substitute for timed Bluebook Math.
Quick reference for linear, quadratic, systems, exponents, and inequalities on Digital SAT Math. Calculator (including Desmos) is allowed on every item; still write the model first. For traps, tool choice, and a tonight drill, use the full Algebra Clinic.
Digital Math Reminders
Modules
Two adaptive Math modules. Protect Module 1 accuracy — it routes Module 2 difficulty.
Tool Check
Clean one-equation algebra → pencil. Intersections / messy systems / graphs → Desmos. Desmos does not carry across modules.
SPR Entry
Negatives allowed. Positive ≤5 characters; negative ≤6 including minus. No %, commas, or $.
Linear Equations
Standard form
Ax + By = C
Slope-intercept
y = mx + b
Point-slope
y − y₁ = m(x − x₁)
Slope
m = (y₂ − y₁)/(x₂ − x₁)
Quadratic Equations
Standard
ax² + bx + c = 0
Factored
a(x − r₁)(x − r₂) = 0
Vertex form
a(x − h)² + k
Quadratic formula
x = [−b ± √(b² − 4ac)] / (2a)
Vertex x
x = −b / (2a)
Systems
Substitution
Solve one variable → substitute → back-substitute.
Elimination
Align opposites → add → solve → substitute.
Graph / Desmos
Intersection = solution. Strong when algebra is messy.
Solution types
One · none (parallel) · infinitely many (same line).
Exponents & Radicals
a⁰ = 1 (a ≠ 0) · a⁻ⁿ = 1/aⁿ
Functions
Notation
f(x) = expression
Linear
f(x) = mx + b
Quadratic
f(x) = ax² + bx + c
Inequalities
|x| < a → −a < x < a
|x| > a → x < −a or x > a
Quick Reference
Distance
d = √[(x₂−x₁)² + (y₂−y₁)²]
Midpoint
((x₁+x₂)/2, (y₁+y₂)/2)
Discriminant
b² − 4ac
Exponential growth (simple model)
A = P(1 + r)ᵗ
Word-problem check
Define the variable as what the stem asks. Percent of what? Discount order? Units before submit.
Next Steps
Formulas do not score by themselves. Run the clinic drill, then a timed Bluebook Math module.