Linear Equations

y = (-1/8)x

x - 4y = 4

To use substitution, I am going to replace the y in the second equation with the expression that is equal to y in the first equation.

x - 4(-1/8)x = 4

x + (1/2)x = 4

(3/2)x = 4

If I multiply both sides by 2/3, I have

x = 4(2/3)

or

x = 8/3

By substituting the value of x into the first equation, I can find the value of y

y = (- 1/8)(8/3)

y = -1/3

The answer is (8/3,-1/3).  Since there is only one answer, the system is consistent, independent.