Explanation:
The slope-intercept form of an euqtion of a line:
y = mx + b
m - slope
b - y-intercept
x = a (a - any real number)
It's the equation of a vertical line. A vertical line has an undefined slope. They also do not have a y-intercept, because they run parallel to the y axis.
Therefore given equations can not write in the slope-intercept form.