Accordinly to the details, i think that A could work.
Answer:(d): y=ax+b (a≠0); (d1)y=-4x+13
because of (d)⊥(d1) --> a.(-4)=-1 --> a=
(d): y=
+b. (d) pass through P(-1;-2) so we have
-2=(1/4).(-1)+b ---> b=
(d) y= 
A is independent while b is dependent.
This is because b is equal to a decreased by 2. Anytime a changes, then b does as well. B can only change in accordance with a.
The answer is 5/2. The equation is already in point slope form. If you recall, the equation for point slope form is y-y1 = m(x-x1) where y1 and x1 are points on the graph, and m is the slope. In the given equation, m is 5/2 so we know it is the slope.
Alternatively, if you are not familiar with the point slope for equation, you can manipulate the equation to the form of y=mx+b where m is the slope and b is the constant. If you solve for y, you get y=5/2x-1 since 5/2 is in the place of m, we know 5/2 is the slope.