Step-by-step explanation
this method works by solving one of the equations , for one of the variables, and then plugging this back into the other equation, "substituting" for the chosen variable and solving for the other
Step 1
we can see that in equation (2) x is isolated, so we just need to replace this value in equation(1)
so
when we got an indetermination, it means the system HAS NOT SOLUTiON
I hope this helps you