Nonlinear Equations in One Variable — Digital SAT SAT Math revision notes
A 4-page visual revision sheet for Nonlinear Equations in One Variable, written for Digital SAT SAT Math. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.
Page 1 as PDFA preview of page 1 — all 4 pages open full size in the app.
Nonlinear Equations in One Variable in one look
quadratics, radicals and rational equations, and the roots that are not really there
Three families, one habit
quadratic: everything ends up as ax^2+bx+c=0. Factor it if the numbers are friendly, use the formula if they are not
radical: the unknown sits under a root sign. Isolate the root, square both sides, and then CHECK every candidate in the original equation
rational: the unknown sits in a denominator. Multiply through to clear the fractions, and then reject anything that made a denominator zero
the habit both of the last two need is the same: squaring and multiplying up can invent solutions that the original equation never had. Substituting back is not optional here
at 95 seconds a question on average across the 44-question, 70-minute Math section, a quadratic you cannot factor within about fifteen seconds should go straight to the graph or to the formula
The lines that solve most of these
if a product is zero, one factor is zero(x-p)(x-q)=0⇒ x=p or x=q
the quadratic formula, always availablex=frac-b±√b^2-4ac2a
the discriminant decides how many real solutionsD=b^2-4ac
the axis of symmetry, and the vertex xx=-b/2a
sum and product of the two solutionsp+q=-b/a, pq=c/a
Page 1 of 4. The full sheet, all 4 pages, opens free in the app.
What this Nonlinear Equations in One Variable sheet covers
These notes are not a standalone PDF. CapCompass plans SAT Math chapter by chapter against your real exam dates and free hours, and when the plan reaches Nonlinear Equations in One Variable the sheet opens inside the study block itself — at the page covering the sub-topic that block is on, with the timer still running. Revision arrives at the moment the plan says revise, instead of having to be gone looking for.