Question

Complete the equation of the line through (4, -8) and (8,5).

Answer 1

I WILL FIND THE GRADIENT FIRST

`m = (y2 - y1)/(x2 - x1) \\ = (5 - ( - 8))/(8 - 4) \\ m = (5 + 8)/(4) \\ m = (13)/(4)`

THE GENERAL EQUATION OF A STRAIGHT LINE IS y=mx+c

I will use the point (8,5)

to find the value of c

`5 = (13)/(4) (8) + c \\ 5 = (104)/(4) + c \\ c = 5 - (104)/(4) \\ c = - (84)/(4) \\ c = -21`

THE EQUATION IS

`y = (13)/(4) x - 21`