Solve this

Given : $3 x+y=19$

$3 x-y=23$

Using Cramer's Rule, we get

$\mathrm{D}=\mid 3 \quad 1$

$3-1 \mid=-3-3=-6$

$\mathrm{D}_{1}=\mid 19 \quad 1$

$23-1 \mid=-19-23=-42$

$\mathrm{D}_{2}=\mid 3 \quad 19$

$3 \quad 23 \mid=(3 \times 23)-(3 \times 19)=3 \times 4=12$

Now,

$\mathrm{x}=\frac{\mathrm{D}_{1}}{\mathrm{D}}=\frac{-42}{-6}=7$

$\mathrm{y}=\frac{\mathrm{D}_{2}}{\mathrm{D}}=\frac{12}{-6}=-2$

$\therefore \mathrm{x}=7$ and $\mathrm{y}=-2$