Question

substitution method -4x+y=6,-5x-y=21​

Answer 1

Answer:

x = -3 , y= -6

Step-by-step explanation:

-4x +y =6_____(1)

-5x-y=21____(2)

add. equation (1),(2)

-4x+y=6

+ -5x-y=21

__________

-9x =27

x = 27/(-9)

x= -3

put value of x in equation (1)

-4x+y=6

-4(-3)+y =6

12+y = 6

y= 6-12

y = -6