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

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Answer 1 · 2016-12-05T20:06:02

$x = 3 and y = 1$ $x = 3 and y = 1$

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.

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

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

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

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

$1 = y$ $1 = y$

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

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