Difficulty: Medium
Correct Answer: x < y
Explanation:
Introduction / Context:
Each variable is governed by a quadratic; we must list all possible roots for x and y, then check whether a single inequality relation holds for every admissible pair (x, y).
Given Data / Assumptions:
Concept / Approach:
Compute discriminants to find exact roots. Then compare the sets: if every x is less than every y, conclude x < y conclusively.
Step-by-Step Solution:
I: D = 48^2 − 4*17*(−9) = 2304 + 612 = 2916 = 54^2x = [−48 ± 54]/(2*17) ⇒ x ∈ {3/17 ≈ 0.1765, −3}II: D = (−32)^2 − 4*13*12 = 1024 − 624 = 400 = 20^2y = [32 ± 20]/(2*13) ⇒ y ∈ {2, 6/13 ≈ 0.4615}Compare every pair: −3 < 0.4615 and −3 < 2; 0.1765 < 0.4615 and 0.1765 < 2.
Verification / Alternative check:
Note the largest x is about 0.1765 while the smallest y is about 0.4615, ensuring x < y for all combinations.
Why Other Options Are Wrong:
“x > y” or “x = y” never occurs with these root sets; “indeterminate” is wrong because the inequality is consistent.
Common Pitfalls:
Missing one root or miscomputing the discriminant can flip the conclusion; compute precisely.
Final Answer:
x < y
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