Free Full-Length GRE Practice Test (Adaptive & Timed)

1. Expand both quantities: - Quantity A: $x^2 + 2x + 1$ - Quantity B: $x^2 - 2x + 1$ 2. Subtract $x^2 + 1$ from both quantities: - Quantity A becomes $2x$ - Quantity B becomes $-2x$ 3. Test cases based on sign: - If $x = 2$ (positive): Quantity A $= 4$, Quantity B $= -4 \implies \text{Quantity A} > \text{Quantity B}$. - If $x = -2$ (negative): Quantity A $= -4$, Quantity B $= 4 \implies \text{Quantity B} > \text{Quantity A}$. Because the relative order flips when $x$ switches signs, the relationship cannot be determined.

Standard ETS trap: examinees unconsciously test only positive integers ($x = 1, 2$), where Quantity A is larger, and fail to test negative values where the inequality inverts.

Always test numbers from the "ZONE F" framework: Zero, One, Negatives, Extremes, and Fractions.

1. Solve for $x$: $$3x - 7 = 2x + 8$$ $$3x - 2x = 8 + 7 \implies x = 15$$ 2. Calculate $x^2 - 10$: $$15^2 - 10 = 225 - 10 = 215$$ Thus, the correct answer is $215$.

Always read the prompt carefully: ETS often asks for an expression like $x^2 - 10$ rather than $x$ itself.

The sentence structure uses the contrast pivot "Although" ("appeared promising") paired with the explanatory elaboration "demonstrating no statistically significant efficacy." The blank must mean failing to produce an effect. "Ineffectual" directly matches this definition.

Identify structural pivot words (Although, Despite, But) to determine if the blank supports or reverses the initial clause.