Respuesta :

Answer:

Step-by-step explanation:

we can write -9 instead of x and y=1 instead of 1

so we write solution again

-9a+1b=-31

-9a-1b=-41

-18a=-72

a=4

we should write 4 instead of a

-9(4)+1b=-31

-36+b=-31

b=5

a=4