# How do you solve #2x + y = -1# and #x - 2y = 7#?

##### 1 Answer

Aug 17, 2015

#### Answer:

x = 1 ; y = - 3

#### Explanation:

2x + y= −1 *_**_*_(1)

x − 2y = 7 ** _**___(2)

2x - 4y = 14 ------------------------(3)

Subtract (3) from (1)

2x + y= −1

2x - 4y = 14

```
5y = - 15
```

```
y = -3
```

Substitute y = - 3 in equation (1)

2x + ( - 3) = - 1

2x - 3 = - 1 Multiply both sides by 5

10x - 15 = - 5

10x = - 5 + 15 = 10

x =

x = 1