Question

Solve the following pair of linear equations

$\frac{2}{\sqrt{x}}$ + $\frac{3}{\sqrt{y}}$ = 2

$\frac{4}{\sqrt{x}}$ - $\frac{9}{\sqrt{y}}$ = -1

• A. 9,8
• B. 4,9
• C. 3,2
• D. $\frac{1}{2}$, $\frac{1}{3}$

Answer 1

The correct option is B

4,9

The pair of equations is not linear. We will substitute $\frac{1}{x}$ as $u^2$ and $\frac{1}{y}$ as $v^2$ then we will get the equation as

$2u+3v=2$

$4u-9v=-1$

We will use method of elimination to solve the equation.
Multiply the first equation by 3, we get

$6u+9v=6$

$4u-9v=-1$

Adding the above two equations we get

$10u=5$

$u=\frac{1}{2}$

Substituting $u$ in above equation we get $v=\frac{1}{3}$

So $x=\frac{1}{u^2}=4$

$y=\frac{1}{v^2}=9$