Which of the following is the equation of the line in the xy-plane that has slope 0
(I) x = 3
(II) y = 3
(III) x + y = 0  Choose the correct choice from the following: A) II B) I C) III D) I&II E) II&III
y =mx+c therefore y-c= mx then m =(y-c)/x   m=0 means y = c constant ..= II   II
<result>A</result>
Which of the following is the equation of the line in the xy-plane that has slope 0
(I) x = 3
(II) y = 3
(III) x + y = 0