Question 366691
a. The line is a vertical line (same x-coordinates).  The equation is x = 3.
b. {{{(5--7)/(-4--8) = (y-5)/(x--4)}}},
{{{3 = (y-5)/(x+4)}}},
{{{3x+12 = y-5}}},
{{{y = 3x+17}}}.