# How do you solve the system 0.4x-0.1y=2, 0.2x+0.5y=1?

Jan 14, 2017

See explanation.

#### Explanation:

The starting system is:

## $\left\{\begin{matrix}0.4 x - 0.1 y = 2 \\ 0.2 x + 0.5 y = 1\end{matrix}\right.$

If we multiply the second equation by $- 2$ the coefficients of $x$ will be opposite numbers:

## $\left\{\begin{matrix}0.4 x - 0.1 y = 2 \\ - 0.4 x - y = - 2\end{matrix}\right.$

Now we can add both sides of the equations to get an euation of 1 variable:

## $y = 0$

Now we have to substitute the calculated value of $y$ to calculate $x$: