Question 1200253
Perpendicular lines have negative reciprocal slopes. You have correctly determined
that the slope of the line through (-6,4) and (-2,5) is 1/4. Thus, the line
through the points (-3,4) and (0,k) has a slope of -4.
-4 = (k-4)/(0-(-3)) -> (k-4)/3 = -4 -> k-4 = -12 -> k = -8.