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\( \left( x+y\right)\) : \( \left( x-y\right)\)= 3 : 5 and xy = positive imply that

A) \(x \) and \( y\) are both positive
B) \(x \) and \( y\) are both negative
C) One of them is positive and one of them is negative
D) No real solutions for \( x\) and \( y\) exist

Correct Answer:




D) No real solutions for \( x\) and \( y\) exist

Description for Correct answer:
Here xy = positive

Either x and y, both are positive or x and y both are negative but from,

\( \Large \frac{x + y}{x - y} = \frac{3}{5}\)

\( \Large 5x + 5y = 3x - 3y \)

\( \Large -2x = 8y \)

x = -4y .... (i)

Equation (i) indicates that either x is + ve or y is -ve

Hence no real solution for x and y exist.

Part of solved CDS Maths(1) questions and answers : Exams >> CDSE >> CDS Maths(1)

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