14.3 Reference Sheet, Desmos, and What This Test Does Not Include

14.3 Reference Sheet, Desmos, and What This Test Does Not Include

Quick Answer: In every Bluebook Math module, a reference sheet, a Desmos calculator, and the Math directions can be opened throughout the 35 minutes. Toggle Desmos between scientific and graphing. The sheet includes formulas you need (rectangle, triangle, box, Pythagorean theorem, triangle-sum 180°) and formulas this exam does not test (circle area and circumference, radian notes). Special right-triangle side pictures on the sheet are optional geometry facts, not trigonometry. Do not prep PSAT 8/9 with sin/cos/tan, circle theorems, rational/radical equations, or sample-inference / margin of error / experiment items.

Geometry is only ≈12.5% of Math. Algebra is ≈42.5% (about 16–18 operational questions). Tools matter, but so does not over-investing in SAT-only Geometry. This OpenExamPrep section is independent study material for the PSAT 8/9. It is not an official College Board publication and does not claim partnership, approval, or exact equivalence with College Board, the SAT Suite, or the PSAT 8/9.

How to open the reference sheet and Desmos

Official Math module directions (the same directions for both modules) say: use of a calculator is permitted for all questions, and a reference sheet, calculator, and these directions can be accessed throughout the test. Directions for answering also appear at the top-left of every question screen. The PSAT 8/9 Student Guide lists a reference sheet (a list of common formulas) and a built-in Desmos calculator among Bluebook Math tools. College Board’s Bluebook tools page adds that the Desmos calculator can be dragged anywhere on the screen and that a formula reference sheet appears on tests with math questions.

Practical habit:

1. Start the Math module and locate the on-screen calculator and reference tools once, before you need them on a hard item.
2. Open the reference sheet when a formula is not automatic—especially 1/2 bh, ℓwh, and c² = a² + b².
3. Open Desmos when arithmetic is messy (large squares, a square root that is not a triple, unit conversion).
4. Close or drag the calculator aside so it does not cover the figure.
5. You may review answers inside a module until time expires. You cannot return to Module 1 after Module 2 starts.

Practice these motions in Bluebook test preview or a full Bluebook practice test—not for the first time on test day. College Board also points students to the public Desmos scientific and graphing calculators for extra familiarity.

Scientific versus graphing Desmos

Students can toggle between scientific and graphing options at any point in the Math section.

For a right-triangle side, scientific is usually faster: type the squares, add, take the square root, and compare with the figure. Graphing is not required to “do geometry.” Switching modes does not cost a submission; it is a view toggle.

Handheld backup: you may bring an approved non-CAS graphing, scientific, or 4-function calculator. CAS (computer algebra system) models are prohibited—if the model name includes CAS, or the device can factor/expand/solve symbolically and return exact symbolic answers, leave it home. Four-function calculators are allowed but not recommended (they often ignore order of operations). You may not use a calculator on Reading and Writing; it goes under the desk for those modules. If a handheld fails, continue with embedded Desmos. You cannot share calculators.

What is on the sheet versus what PSAT 8/9 assesses

The SAT Suite uses one Math reference sheet. PSAT 8/9 students see circle formulas even though this exam does not assess circle skill/knowledge. Use the sheet as a menu, not as a syllabus.

Worked optional 45-45-90 (not trig). A square has side s = 7. Its diagonal is the hypotenuse of an isosceles right triangle: 7√2. You can also use Pythagorean theorem: 7² + 7² = 98, and √98 = 7√2. Same geometry, no sine.

Worked optional 30-60-90 (not trig). Short leg x = 4 (opposite 30°). Then the long leg is 4√3 and the hypotenuse is 8. If you only remember Pythagorean theorem, 4² + (4√3)² = 16 + 48 = 64 = 8². Still no cosine.

If a question looks like it wants sin/cos/tan, you are looking at the wrong toolkit for this test. Return to triangle sum, parallel-line angle pairs, or a² + b² = c².

Official out-of-scope list (do not pad your 8/9 plan)

The Assessment Framework’s variations by testing program are the line between useful review and wasted hours:

1. Trigonometry skills and knowledge are not assessed on PSAT 8/9. No sine, cosine, tangent, unit circle, or trig identities.
2. Skills and knowledge associated with circles are assessed only on the SAT. No inscribed-angle theorems, arc length as a circle testing point, or “the radius is perpendicular to the tangent” as 8/9 content. Seeing π on the sheet is not a promise of a circle item.
3. Rational and radical equations are not represented on PSAT 8/9 (Advanced Math). You still solve quadratics and other in-scope nonlinear equations; you do not need a rational-equation unit for this sitting. See nonlinear equations.
4. Inference from sample statistics, margin of error, and evaluating statistical claims about observational studies and experiments are later SAT Suite Problem-Solving and Data Analysis testing points, not PSAT 8/9. This exam’s PSD list stops at ratios/rates/units, percentages, 1-variable data, 2-variable data, and probability/conditional probability.

Other Bluebook Math notes that are in force even when a formula is out of scope:

• Figures are drawn to scale unless otherwise indicated—use that as a sanity check, not as a substitute for Pythagorean arithmetic.
• Figures lie in a plane unless otherwise indicated; a prism is still drawn as a picture of a 3D object.
• SPR entry: up to 5 characters for a positive answer and 6 with a negative sign; mixed numbers as improper fractions or decimals; no %, comma, or $; if a fraction does not fit, enter a decimal; decimals truncate or round at the fourth digit.

How to spend Geometry time

Operational Math on PSAT 8/9 is 40 questions. Geometry is about 4–6 of them. A sensible split:

• Master area and volume formulas and one composite add/subtract move.
• Master lines, angles, and triangles: 180°, vertical/linear pair, parallel + transversal, Pythagorean triples and one non-triple square-root item.
• Click the reference sheet and Desmos once each in Bluebook practice so the motion is automatic.
• Stop. Put remaining hours into Algebra (the largest domain) and the in-scope PSD skills. Do not build a circle-theorem or trig deck for this test.

/practice/psat-89Practice questions with detailed explanations