Question

How do you solve the system `y = 3x - 4` and `2x - y = 1`?

Answer 1

If you substitute the expression for `y` given by the first of these equations into the second you find:

`1 = 2x - y = 2x - (3x - 4) = -x+4`

Add `x-1` to both ends to get:

`x = 3`

Then substitute this value for `x` into the first equation to get:

`y = 3x-4 = (3xx3)-4 = 9-4 = 5`