Equations And Inequations Ques 85

I. $2 x^{2}-11 x+15=0$

II. $2 y^{2}-15 y+28=0$

Directions : In the following questions two equations numbered I and II are given. You have to solve both the equations and give answer

(1) if $x>y$

(2) if $x \geq y$

(3) if $x<y$

(4) if $x \leq y$

(5) if $x=y$ or the relationship between $x$ and $y$ cannot be established.

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Correct Answer: 85.(3)

Solution: (3) I. $2 x^{2}-11 x+15=0$

$\Rightarrow 2 x^{2}-6 x-5 x+15=0$

$\Rightarrow 2 x(x-3)-5(x-3)=0$

$\Rightarrow(x-3)(2 x-5)=0$

$\Rightarrow x=3$ or, $\frac{5}{2}$

II. $2 y^{2}-15 y+28=0$

$\Rightarrow 2 y^{2}-8 y-7 y+28=0$

$\Rightarrow 2 y(y-4)-7(y-4)=0$

$\Rightarrow(y-4)(2 y-7)=0$

$\Rightarrow y=4$ or, $\frac{7}{2}$

Clearly, $x<y$