Solve the simultaneous equation using substitution method x-y=8 and 4x+y=4

x - y = 8

Add y to both sides

x = 8 + y

4x + y = 4

Substitute the value of x from the first equation in

4 (8 + y) + y = 4

Simplify and solve

32 + 4y + y = 4

32 + 5y = 4

5y = - 28

y = - 5.6

Now put that value of y into the first equation

x = 8 + (-5.6)

x = 2.4