Let x be the greater real root of 225x^2 − 4 = 0 and y be the (unique) real solution of 15y + 2 = 0 (interpreting √225 · y + 2 = 0). Compare x and y.

Difficulty: Easy

Correct Answer: If x > y

Explanation:


Introduction / Context:
The second relation was typographically unclear. Using Recovery-First Policy, we interpret √225 y + 2 = 0 as (√225)·y + 2 = 0 ⇒ 15y + 2 = 0. We then solve both and compare the numeric values using the greater real root convention for the quadratic.


Given Data / Assumptions:

  • 225x^2 − 4 = 0 ⇒ x has two symmetric real roots; take the greater one.
  • 15y + 2 = 0 ⇒ single solution y.


Concept / Approach:
Solve each: isolate x^2 and y. For comparison, evaluate numerically and select the correct inequality.


Step-by-Step Solution:

225x^2 − 4 = 0 ⇒ x^2 = 4/225 ⇒ x = ±2/15; greater root x = 2/15.15y + 2 = 0 ⇒ y = −2/15.Compare: 2/15 > −2/15 ⇒ x > y.


Verification / Alternative check:
Decimal check: x ≈ 0.133…, y ≈ −0.133…, confirms the inequality.


Why Other Options Are Wrong:
They reverse the sign relation or claim equality, which is false given the computed values.


Common Pitfalls:
Misreading √225 y as √(225y); the intended linear form is (√225)·y.


Final Answer:
If x > y

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