Answer:
y = x - 3
Step-by-step explanation:
The 2-point form of the equation of a line can be written as ...
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
For the given points, this becomes ...
y = (1-2)/(4-5)(x -5) +2 . . . . . fill in the numbers
y = (-1)/(-1)(x -5) +2 . . . . . . . . simplify a bit
y = x -5 +2 . . . . . . . . . . . . . . simplify more
y = x -3 . . . . the equation of the line