Question 988538
You can work entirely in slope-intercept form as the equations you are given.
{{{y=mx+b}}}
{{{y-mx=b}}}
{{{b=y-mx}}} for any point (x,y).


For parallel, as question #1, keep same slope, 3.
For perpendicular, as question #2, take the negative reciprocal of slope, meaning  {{{-1/2}}}.