Let

Then let be the two planes

Find two distinct points on the intersection of and .

First, we have

So, the points in the intersection are those such that

From the first set of equations we have the equations

The second equation implies , and so the first equation implies . Then,

From the second set of equations we have

The first equation implies . The second equation then implies

Therefore, . So, finally we have

Therefore, we obtain the Cartesian equation

Thus, the set of points in the intersection of these two planes are those points such that

In this case is arbitrary. First, taking we have

These implies and . On the other hand, taking we have

These imply and . Hence, we have

how did you assume this.(First, taking z = 6 we have) and then ( On the other hand, taking z = 17 we have)

please let me know as soon as possible . THanks

You can choose any z you like and you will find an x,y solving the equations.