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SSC CGL 2025 PYQ — Question 28

SSC CGL Tier II - 18 January 2025 - Shift I • Quantitative Aptitude • Q28

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If x=8+5x=8+\sqrt{5} and y=8−5y=8-\sqrt{5} then the value of x2+y2x^2+y^2 is:

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Correct answer: B

Explanation

The correct answer is option 2 i.e. 138.

x = 8 + √5

⇒ x2 = (8 + √5)2 = 69 + 16√5

y = 8 - √5

⇒ y2 = (8 - √5)2 = 69 - 16√5

Now, x2 + y2 = (69 + 16√5) + (69 - 16√5) = 138

Therefore, the value of x2 + y2 is 138.