Mr. Martin and his son, Luke, decide to walk a 12 kilometer trail. Mr. Martin takes a 1-hour head start and walks at a pace of 3 km/hr. Explain how fast Luke should walk to reach the end of the trail in 3 hours, the same time as Mr. Martin.

It will take Mr. Martin 4 hours to walk the trail, and Luke should walk faster than Mr. Martin. Using the equation 12 = (3)(x), Luke should walk 4 km/hr to finish the trail in 3 hours.

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