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

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Answer 1 · 2018-03-11T12:40:22

$x=-3 and y=7$

This is one of the best forms you can have for a system of equations. Note that they each have a single $y$ term...

Graphically it means they each represent a straight line and the solution is the point of intersection of the lines.

Write each equation in slope-intercept form, ie with $y$ on one side.

$y = -x+4 " and "y= -3x-2$

Now, as $y = y$ , equate the right sides of the equations:

$-x+4 =-3x-2$

$3x-x=-2-4$

$2x = -6$

$x=-3$

Now you can use one equation to find a value for $y$ and the
other equation to check.

$y = -(-3)+4" "and" "y =-3(-3)-2$
$y= 3+4color(white)(wwwwwwwwwwww.w)y = 9-2$
$y =7color(white)(wwwwwwwwwwwwwwww)y=7$

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