Find an equation for (a) the vertical line and (b) the horizontal line through the given point.
(-3.14,0)
The general equation for a line is
Ax + By + C = 0
For a vertical line, B=0.
For a horizontal line, A=0.
The line that passes through (x0,y0) is
A(x-x0) + B(y-y0) = 0
Can you take it from here, knowing that (x0,y0) = (3.14, 0), i.e.
x0=3.14,
y0=0