September 13 2025 DSAT – Test 9I: Sample Questions & Full Analysis

Expert Breakdown of the September 2025 Digital SAT (Test 9I)

Welcome to the allsatpapers.com expert analysis! As specialists in official test materials, we know that success on the Digital SAT comes from practicing with real, official exams. The 13 September 2025 DSAT (Test 9I) is a key test form from this administration. It provides a crucial look at the types of questions, vocabulary, and mathematical reasoning skills the College Board is currently using to challenge students.

This post will provide a deep dive into this specific test, quoting key passages that customers often search for to identify the exam they need. Let's analyze what makes Test 9I a vital study tool.

Section 1: Reading & Writing Module 1 (Key Passages)

The first R&W module is designed to set your baseline. As requested, we have quoted the first two questions in full, as these are the most common passages users search for to identify this test.

Section 1: Reading & Writing Module 2 (Adaptive) Analysis

This module's difficulty adapts based on your performance in Module 1. The questions become more complex, testing more nuanced vocabulary and text structures. Here are some key passages from Module 2 of Test 9I.

Section 2: Math Module 1 Analysis

The first math module on Test 9I features a standard mix of algebra, data analysis, and geometry. The focus is on foundational skills and straightforward application.

Core Concepts on Display

• Rates (Question 1): A very straightforward calculation. A pigeon flies at an average speed of 16 meters per second. The question asks for the distance flown in 3 seconds. This is a direct application of the formula $\text{Distance} = \text{Speed} \times \text{Time}$.
  $\text{Distance} = 16 \text{ m/s} \times 3 \text{ s} = 48 \text{ meters}$. This is choice (C).
• Polynomial Factors (Question 12): This question tests the relationship between a polynomial's roots and its factors. The graph passes through (has x-intercepts at) $(-4,0)$, $(3,0)$, and $(5,0)$. The roots are $x = -4$, $x = 3$, and $x = 5$. The corresponding factors are $(x - (-4))$, $(x - 3)$, and $(x - 5)$, which simplify to $(x + 4)$, $(x - 3)$, and $(x - 5)$. The only choice that matches one of these factors is (C) $x-3$.
• Systems of Equations (Question 14): This question asks for the number of solutions to the system:
  $8x + 32y = 38$
  $12x + 48y = 57$
  To check for the number of solutions, we can find the slope and y-intercept of each line.
  Line 1: $32y = -8x + 38 \rightarrow y = (-8/32)x + 38/32 \rightarrow y = (-1/4)x + 19/16$
  Line 2: $48y = -12x + 57 \rightarrow y = (-12/48)x + 57/48 \rightarrow y = (-1/4)x + 19/16$
  Since the slopes are identical ($-1/4$) and the y-intercepts are identical ($19/16$), the two lines are the same. Therefore, they intersect at every point, meaning there are (B) Infinitely many solutions.

Section 2: Math Module 2 (Adaptive) Analysis

This module increases the complexity, requiring multi-step problem-solving and a deeper understanding of algebraic structures.

Advanced Applications

• Polynomial Operations (Question 1): A test of careful subtraction: $(2x^3 - 3x + 5) - (7x^6 + 7x - 4)$. The most common error is failing to distribute the negative sign.
  $2x^3 - 3x + 5 - 7x^6 - 7x + 4$
  Combine like terms: $-7x^6 + 2x^3 - 10x + 9$. This matches choice (C).
• Circle Equations (Question 9): This question tests your ability to manipulate the standard circle equation, $(x-h)^2 + (y-k)^2 = r^2$.
  The equation for Circle A is $(x-2)^2 + (y-3)^2 = 25$. From this, we know the center is $(2, 3)$ and the radius ($r$) is $\sqrt{25} = 5$.
  Circle B has the same center $(2, 3)$ but a radius that is "twice the radius of circle A," so the new radius is $2 \times 5 = 10$.
  The new $r^2$ is $10^2 = 100$.
  The equation for Circle B is (D) $(x-2)^2 + (y-3)^2 = 100$.
• Geometry (Question 10): This question asks for the area of a square given its diagonal. The diagonal ($d$) is $\frac{196\sqrt{2}}{2} = 98\sqrt{2}$.
  Method 1 (Formula): The area of a square is $A = d^2 / 2$.
  $A = (98\sqrt{2})^2 / 2$
  $A = (98^2 \times 2) / 2$
  $A = 98^2 = 9604$.
  Method 2 (Pythagorean): Let the side length be $s$. Then $s^2 + s^2 = d^2$.
  $2s^2 = (98\sqrt{2})^2$
  $2s^2 = 98^2 \times 2$
  $s^2 = 98^2 = 9604$.
  Since the area is $s^2$, the area is (D) 9,604.
• Advanced Quadratics (Question 19): This question tests the "product of solutions" rule.
  The equation is: $\frac{1}{78}x^2 + (s - \frac{1}{78}t)x - st = 0$.
  For any quadratic $ax^2 + bx + c = 0$, the product of the solutions is $c/a$.
  In this equation, $a = \frac{1}{78}$ and $c = -st$.
  $\text{Product} = c/a = \frac{-st}{1/78} = -78st$.
  The problem states the product is $-2kst$.
  Set them equal: $-2kst = -78st$.
  Divide both sides by $-2st$: $k = 39$.
  The answer is 39.

Overall Difficulty and Analysis of Test 9I

After a comprehensive review of all four modules, here is our expert assessment of the 13 September 2025 (9I) DSAT:

• Overall Difficulty: Medium-Hard.
• Analysis: This test is another "form" of the September 13, 2025 exam, and it is highly similar, but not identical, to Tests 9A-9H. It pulls many of the same questions from the College Board's item bank, including the "maize/corn" problem, the "Thomas Hardy" passage, and the circle equation problem. This confirms that mastering the concepts from one form (like 9A or 9E) directly prepares you for all other forms from that day.
• Reading & Writing: The section is of Medium difficulty. The vocabulary in Module 1 ("magnify," "varies from") and Module 2 ("conspicuous," "synthesis") is very standard and heavily clued by the context. The logic is straightforward, and the grammar questions test core rules.
• Math: This section is Hard. While Module 1 is standard, Module 2 contains several high-difficulty problems designed to differentiate top scorers. The circle equation (M2 Q9), the area-from-diagonal (M2 Q10), and the advanced product-of-solutions (M2 Q19, $k=39$) are all classic examples of high-level SAT reasoning that require deep conceptual knowledge, not just simple calculation.

Why This Practice Test is Essential For Your Prep

DSAT Test 9I (13 September 2025) is a perfect snapshot of the current Digital SAT. It clearly shows the test's emphasis on:

• Vocabulary in Context: You must be able to use contextual clues to determine the precise meaning and function of a word.
• Evidence-Based Reading: The ability to read a short passage or graph and find the one piece of evidence that directly supports a claim is critical.
• Algebraic Fluency: The Math section is dominated by algebra. Fluency in factoring, solving linear equations, and setting up inequalities from word problems is non-negotiable.
• Multi-Step Problem Solving: The hardest questions (like the product of solutions and area problems in Module 2) are not testing obscure concepts. They are testing your ability to execute multiple foundational concepts in the correct order.

Studying with an official past paper like Test 9I is the single best way to build the skills and pattern recognition needed to excel on test day. Analyzing your mistakes on this exam will show you exactly what to focus on in your remaining prep time.