Question

Find the solution for the following pair of equations
$3x-8y=4$
$x=2y$

• A. $(-4,-2)$
• B. $(2,1)$
• C. $(0,-\frac{1}{2})$
• D. $(0,0)$

Answer 1

The correct option is A $(-4,-2)$

Given pair of equations
$3x-8y=4\dots \left(i\right)$
and $x=2y\dots \left(ii\right)$

Step 1: Find the value of y
Substituting $x=2y$ in $\left(i\right),$ we get
Equation $\left(i\right)$ $\to$ $3\left(x\right)-8y=4$
$3\left(2y\right)-8y=4$
$\Rightarrow 6y-8y=4$
$\Rightarrow -2y=4\Rightarrow y=-2$

Step 2: Now, Find the value of x
Substitute $y=-2$ in equation $\left(ii\right)$
Equation $\left(ii\right)$ $\to$ $x=2\left(y\right)$
$x=2(-2)$
$\Rightarrow x=-4$
$\therefore x=-4,y=-2$

$\therefore$ Required solution for the given pair of equations is $(-4,-2)$