# How do you solve 3x+4y=-10 and x-4y=2?

Mar 21, 2016

x = -2; y = -1

#### Explanation:

First solve for $x$ by adding the two equations:

$3 x + 4 y = - 10$
+$x - 4 y = 2$

This gives you:
$4 x = - 8$, so $x = - 2$

Then you can solve for $y$ by either plugging $- 2$ in for $x$ or by multiplying the second equation by $- 3$ and adding the two equations again:

$$    3x + 4y = -10


+$- 3 \left(x - 4 y\right) = 2 \cdot - 3$

This gives:
$16 y = - 16$, so $y = - 1$

You can verify your answer by plugging $- 2$ in for $x$ and $- 1$ in for $y$ in both equations.