How do you solve $3 x + y = 4$ $3x + y = 4$ and $2 x + y = 4$ $2x + y = 4$ ?

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Answer 1 · 2015-11-27T12:28:34

The solution for the system of equations is
$x = 0, y = 4$ $color(blue)(x=0,y=4$

$3 x + y = 4$ $3x+color(blue)(y)=4$ ......equation $(1)$ $(1)$
$2 x + y = 4$ $2x+color(blue)(y)=4$ ......equation $(2)$ $(2)$

Solving by elimination

Subtracting equation $1$ $1$ from $2$ $2$ would result in elimination of $y$ $color(blue)(y$

$3x+cancelcolor(blue)(y)=4$
$-2x-cancelcolor(blue)(y)=-4$

$color(blue)(x=0$

Substituting $x$ in equation $1$ to find $y$ :

$3x+y=4$

$3 * 0 +y=4$
$0 +y=4$
$color(blue)(y=4$

How do you solve 3x + y = 43x+y=43x + y = 4 and 2x + y = 42x+y=42x + y = 4?