What number is represented by the point B which represents the number 2

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c

i believe that the answer is

b. y-1=-2(x-4)

hope this !