Question

Solve the simultaneously equations $2y-x=0,10x+15y=105$

Answer 1

The given equations can be solved by substitution method.

$2y-x=0$

$2y=x$

$\therefore x=2y$

$10x+15y=105$ ………….$\left(1\right)$

Substitute $x$ value in $\left(1\right)$

$10x+15y=105$

$\Rightarrow 10\left(2y\right)+15y=105$

$\Rightarrow 20y+15y=105$

$\Rightarrow 35y=105$

$\Rightarrow y=\frac{105}{35}$

$\Rightarrow y=3$

Sub y$=3$ in $x$

$x=2y$

$\Rightarrow x=2\left(3\right)$

$\Rightarrow x=6$

$\therefore x=6$ and $y=3$.