Question 787065
Using gradient formula:
y2 - y1/x2 - x1
1 - 7/8 - 2
-6/6
= -1
This the slope (gradient) of the line.
Using the equation:
y = mx + c  with one of the coordinates
say, (2,7)
y = mx + c
7 = -1(2) + c
c = 9
Equation:
y = -x + 9
Hope this helps.
:-)