When constructing a slope field for on a lattice of integer points

MATHEMATICS · Single correct · AP · Calculus AB · Differential Equations · Differential Equations

Problem

When constructing a slope field for

\dfrac{dy}{dx}=\dfrac{y}{x}

on a lattice of integer points, which vertical line(s) in the

xy

-plane must be left blank because the slope is undefined there? (a) only

y=0

(b) both

x=0

and

y=0

x=0

(d) no entire vertical line—just the point

(0,0)