Question

Any chance someone can explain this ?

Answer 1

(-9, 5)

Explanation:

there are 2 variable: x and y

eliminate one of the variables for example y

-x - y = 4

-2x - y = 13 multiply this equation by (-1)

-x - y = 4

2x + y = -13

add both equations

2x-x-y+y = 4-13

x = -9

substitute x = -9 in the first equation

-(-9)-y = 4

9 - y = 4 subtract 9 from both sides

-y = 4 - 9

-y = -5 multiply by (-1)

y = 5