Answer:

Explanation:
The first equation can be rearranged by subtracting y from both sides. This gives you x = 4 - y.
The second equation is x = y - 1
Therefore, as both equations are equal to x, you can say that they are equal to each other, so 4 - y = y - 1.
If you add 1 to each side, you get 5 - y = y
If you add y to each side, you get 5 = 2y
Divide both sides by 2 to get y = 5/2
Now you can substitute 5/2 for y. For example, the second equation becomes x = 5/2 - 1
x is therefore 3/2
This can be written as
, which is the final answer.