Answer: I know it 4 but I don’t know the equation for it, I can only help you this far.(hope it help)
Step-by-step explanation:
(1,4) and (-2,-8)
(x is the first number of the point which is 1 and -2, y is the second number of the point which is 4 and -8.)
(x1 is 1, it alway the first point they tell you on the problem like (1,-4) is on the problem first so it gonna be x1 and y1, for x2 it -2, it alway the second point in the problem like (-2,-8) is the second point they tell you so it gonna be y1 and y2.)
Do x2 - x1 and y2 - y1(y/x)
-8 - 4/-2 - 1 = -12/-3
-12/-3 divide top and bottom by -3, that would equal to 4