# How do you solve 3y=-2x, y=x-5 by substitution?

## List item

Dec 6, 2016

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

#### Explanation:

Step 1) Because the second equation is already solved for $y$ we can substitute $x - 5$ for $y$ in the first equation and solve for $x$:

$3 \left(x - 5\right) = - 2 x$

$3 x - 15 = - 2 x$

$3 x - 15 + 15 + 2 x = - 2 x + 15 + 2 x$

$3 x - 0 + 2 x = 0 + 15$

$5 x = 15$

$\frac{5 x}{5} = \frac{15}{5}$

$x = 3$

Step 2) Substitute $3$ for $x$ in the second equation and calculate $y$:

$y = 3 - 5$

$y = - 2$