How do you solve the system of equations $3x + y = 10$ and $x - y = 2$ ?

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Answer 1 · 2016-12-05T20:06:02

$x = 3 and y = 1$

This is the best scenario you can get with a system of equations. The y-terms are additive inverses which means they add to zero.

$" "3x +y = 10$ ................................A
$" "x -y = 2$ .................................B

$A + B" "4x = 12" "$ there is only x, you can solve for x.
$" "x = 3$

Substitute 3 for x in one of the equations - let's use B

$x-y = 2$
$3 -y = 2$
$3-2 = y$

$1 = y$

Check: $3x+y = 10$
$3(3) + (1)$
$=10$

How do you solve the system of equations 3x + y = 103x + y = 10 and x - y = 2x - y = 2?