An astronomer wishes to measure on a photograph the distance between the image of a certain star and three star other star images nearby, if 8 images are nearby how many choices of the three stars does he have?

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

its adding 5.5 each time

step-by-step explanation: