How do you solve the system of equations: x + 3y = 1 and -2x + y = -23?

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Answer 1 · 2015-08-08T06:31:50

The solution for the system of equations is
$color(blue)(x=10, y=-3$

$x + 3y = 1$ , multiplying this equation by $2$

$color(blue)(2x) +6y=2$ ...............equation $(1)$

$-color(blue)(2x) + y = -23$ .....equation $(2)$

Now , we can solve by elimination , upon addition of the two equations $color(blue)(2x$ gets eliminated.

$cancelcolor(blue)(2x) +6y=2$

$-cancelcolor(blue)(2x) + y = -23$

$7y =-21$
$color(blue)(y=-3$

Now, we can find $x$ by substituting the value of $y$ in equation $(1)$

$x + 3y = 1$

$x=1-3y$

$x=1-(3*(-3))$

$color(blue)(x=10$