Difficulty: Medium
Correct Answer: x > y
Explanation:
Introduction / Context:We compare any root x from the first quadratic with any root y from the second. If every x exceeds every y (or vice versa), then the relationship is determined. Compute all roots and compare the ranges systematically.Given Data / Assumptions:
Concept / Approach:Find both roots of each quadratic precisely. Determine the interval of possible x values and the interval of possible y values. If the minimum x is greater than the maximum y, then x > y for all combinations.
Step-by-Step Solution:
I: Divide by 2 ⇒ 8x^2 + 10x + 3 = 0. Δ = 10^2 − 4*8*3 = 100 − 96 = 4 ⇒ √Δ = 2.x = [−10 ± 2]/(16) ⇒ x ∈ {−12/16 = −0.75, −8/16 = −0.5}.II: Divide by 2 ⇒ 5y^2 + 19y + 12 = 0. Δ = 19^2 − 4*5*12 = 361 − 240 = 121 ⇒ √Δ = 11.y = [−19 ± 11]/(10) ⇒ y ∈ {−30/10 = −3, −8/10 = −0.8}.Compare ranges: min(x) = −0.75, max(x) = −0.5; min(y) = −3, max(y) = −0.8. Since −0.75 > −0.8 and −0.5 > −0.8, every x is greater than every y.Verification / Alternative check:Test all combinations explicitly: {−0.75, −0.5} minus {−3, −0.8} ⇒ all differences are positive.
Why Other Options Are Wrong:
Common Pitfalls:Arithmetic errors in discriminants or sign mistakes when dividing. Always simplify first to reduce errors.
Final Answer:
x > y
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