They're all in standard form; it's probably easier just to solve for the line than check the points in each one.
The point-point form of a line through (a,b) and (c,d) is
(c-a)(y-b) = (d-b)(x-a)
So here (a,b)=(-1,2), (c,d)=(3,1) so
(3 - -1)(y - 2) = (1 - 2)(x - -1)
4y - 8 = -x - 1
x + 4y = 7
Answer: B
Check:
-1 + 4(2) = 7, good
3 + 4(1) = 7, good
Answer:
true...................
(-3)(-1)
- and - = + positive
=3
Answer: 3
