Let's look at the first equation:
We'll write the variable y in terms of x and then the variable x in terms of y. First:
From here:
and
Doing a similar procedure with the other two equations we'll get:
From
and
From
and
In sumary, let's go over each of the equations and check that the values we got are correct.
From the equation
The answers we got are:
Let's plug these values in the equation to verify our result
Doing all the operations we'll get:
Which is what we started with, so the solutions are correct.
Similarly, for the equation