What s the equation of the line that passes through the points (1, 2/3) and (-1, -1)?

1 Answer
Nov 5, 2017

y = 5/6 x - 1/6

Explanation:

y - y1 = m ( x - x1 )

point 1 : ( 1 , 2/3 )
point 2: ( -1 , -1 )
The numbering of the points is arbitrary; just be consistent.

m can be solved as:
( y2 - y1 ) / ( x2 - x1 )

m = ( -1 - 2/3 ) / ( -1 - 1 )
m = 5/6

y - 2/3 = 5/6 (x - 1)
y = 5/6 x - 5/6 + 2/3
y = 5/6 x - 1/6

graph{y = 5/6 x - 1/6 [-6.21, 13.79, -1.64, 8.36]}