How do you solve by substitution $3x + 2y = 2$ and $-2x + y = 8$ ?

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Answer 1 · 2015-06-09T15:14:54

The solution for the system of equations is
$color(red)(x =-2 , y =4$

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

$-2x + y = 8$
$y =color(red)( 8 +2x$ ............equation $(2)$

Substituting equation $(2)$ in equation $(1)$

$3x + 2y = 2$
$3x + 2color(red)((8+2x)) = 2$
$3x + 16 +4x = 2$
$7x= -14$
$color(red)(x=-2$

Substituting $x$ in equation $(2)$ to find $y$

$y = 8 +2x$
$y = 8 +2.(-2)$
$y = 8 -4$
$color(red)(y = 4$

How do you solve by substitution 3x + 2y = 23x + 2y = 2 and -2x + y = 8-2x + y = 8?