# How do you solve 9x - 3y = 3 and 3x + 8y = -17?

Sep 5, 2015

The solution is
color(blue)(x=-1/3, y=-2

#### Explanation:

$\textcolor{b l u e}{9 x} - 3 y = 3$..........equation $1$

$3 x + 8 y = - 17$, multiplying the equation by $3$
$\textcolor{b l u e}{9 x} + 24 y = - 51$......equation $2$

Solving by elimination .
Subtracting equation $2$ from $1$ results in elimination of color(blue)(9x

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

$- \cancel{\textcolor{b l u e}{9 x}} - 24 y = + 51$

$- 27 y = 54$
color(blue)(y=-2

Finding $x$ by substituting $y$ in equation $1$
$9 x - 3 y = 3$

$x = \frac{3 + 3 y}{9}$

$x = \frac{3 + 3 \cdot \left(- 2\right)}{9}$

$x = \frac{3 - 6}{9}$

$x = \frac{- 3}{9}$

color(blue)(x =-1/3