Question

Solve the systems by the addition method 2x + y = - 1x - 2y = - 4

Answer 1

Answer:

x = -6/5

y =7/5

Step-by-step explanation:

2x + y = - 1

x - 2y = - 4

Multiply the first equation by 2 so we can eliminate y

2(2x + y = - 1)

4x + 2y = -2

Add this to the second equation

4x + 2y = -2

x - 2y = - 4

---------------------

5x + 0y = -6

Divide by 5

5x/5 = -6/5

x = -6/5

Multiply the second equation by -2 so we can eliminate x

-2(x - 2y = - 4)

-2x+4y = 8

Add this to the first equation

2x + y = - 1

-2x+4y = 8

---------------------

0x + 5y = 7

Divide by 5

5y/5 = 7/5

y =7/5