Question

The equations $x-y=0.9$ and $\frac{11}{x+y}=2$ have the solution

• A. $x=5,y=1$
• B. $x=3.2$ and $y=2.3$
• C. $x=3$ and $y=2$
• D. none of these

Answer 1

Answer: (B)

$x=3.2$ and $y=2.3$

The equation are
$x-y=0.9$
$\Rightarrow x=0.9+y$ .....(1)
$\frac{11}{x+y}=2$
$\Rightarrow 2x+2y=11$ .....(2)
Put the value of $x$ in eq(2)
$\Rightarrow 2(.9+y)+2y=11$
$\Rightarrow 1.8+2y+2y=11$
$\Rightarrow 4y=9.2$
$\Rightarrow y=2.3$
$\Rightarrow x=.9+y\Rightarrow x=.9+2.3=3.2$
$\therefore x=3.2,y=2.3$