# How do you solve x + y + 3 and 2x + 3y = 9?

Sep 5, 2015

The solution is
color(blue)(x=-18, y=15

#### Explanation:

Solving assuming that the first equation : $x + y + 3 = 0$

$x + y = - 3$, multiplying this equation by 2:
$\textcolor{b l u e}{2 x} + 2 y = - 6$......equation $1$

$\textcolor{b l u e}{2 x} + 3 y = 9$............equation $2$

Solving by elimination.

Subtracting equation $2$ from $1$ eliminates color(blue)(2x

$\cancel{\textcolor{b l u e}{2 x}} + 2 y = - 6$
$- \cancel{\textcolor{b l u e}{2 x}} - 3 y = - 9$

$- y = - 15$
color(blue)(y=15

Finding $x$ by substituting the value of $y$ in equation $1$
$x + y = - 3$
$x = - 3 - y$
$x = - 3 - 15$
color(blue)(x=-18