Answer
$y^{2}+z^{2}=1$
a circle of radius 1, centered at the origin, in the yz-plane.
Work Step by Step
$x^{2}+y^{2}+z^{2}=1$
is a sphere centered at the origin, radius 1.
$x=0$ is the yz-plane.
The equation of their intersection is obtained by substituting $x=0$ into the equation of the sphere:
$y^{2}+z^{2}=1$
a circle of radius 1, centered at the origin, in the yz-plane.
