How do solve the following linear system?: $3 x - 2 y = 4, 3 y = 15 - x$ $3 x-2y=4 , 3y = 15 -x$ ?

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Answer 1 · 2016-01-12T17:37:07

The solution for the system of equation is
$x = \frac{42}{11}, y = \frac{41}{11}$ $color(blue)(x=42/11 ,y=41/11$

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

$x + 3 y = 15$ $x + 3y=15$ , multiplying by $3$ $3$
$3 x + 9 y = 45$ $color(blue)(3x) + 9y=45$ .....equation $(2)$ $(2)$

Solving by elimination

Subtracting equation $2$ $2$ from $1$ $1$

$cancelcolor(blue)(3x) -2y=4$
$-cancelcolor(blue)(3x) - 9y=-45$

$-11y = -41$

$color(blue)(y = 41/11$

Finding $x$ from equation $2$

$x + 3y=15$

$x =15 - 3y$

$x =15 - 3 xx 41/11$

$x =15 - 123/11$

$x =165/11 - 123/11$

$color(blue)(x =42/11$

How do solve the following linear system?: 3 x-2y=4 , 3y = 15 -x 3x−2y=4,3y=15−x 3 x-2y=4 , 3y = 15 -x ?