Question

$3x-5y-4=0$ and $9x=2y+7$; solve it with the elimination method.

Answer 1

$3x-5y-4=0$

$3x-5y=4$ (i)

$9x=2y+7$

$9x-2y=7$ (ii)

Multiplying (i) with 3 we get:

$9x-15y=12$

we get, $y=-\frac{5}{13}$

Putting value of $y$ in the equation.

$\begin{array}{rcl}9x-2\left(\frac{-5}{13}\right)& =& 7\\ 9x+\frac{10}{13}& =& 7\\ 9x& =& 7-\frac{10}{13}\\ 9x& =& \frac{81}{13}\\ x& =& \frac{9}{13}\end{array}$

Hence, the value of $x$ is $\frac{9}{13}$.