B) y= -1/2x -4
1) Let's start by picking two points from that line: (0,3) and (-2,-1). Now we can plug them into the slope formula and find out the slope of that line:

2) Examining that graph we can see that when x=0 y=3, so the linear coefficient b is 3. Therefore we can write the equation as y= 2x-3.
2.2) Since the question wants a perpendicular line, then the slope of this perpendicular line must be reciprocal and opposite to m=2, so:

So, plugging the given point (6,-7) we can find out the linear coefficient of that perpendicular line:
y=mx +b
-7 = 6(-1/2) +b
-7 =-3 +b
-7+3 = b
b=-4
3) Hence, the answer is y= -1/2x -4