Can anyone help me find the intercept of this

x^2y-x^2+4y=0

My second question is find the points of intersection of the graphs of the equations

analytically.

x^2+y^2=5

x-y=1

I know you have to set them to y so they can be equal to each other.

So I did y=x-1

But how would I do y^2=-x^2+5 ?