The point directly between the two points will definitely be on the line, so find the midpoint
of the two points. Midpoint = = (4, 2). Check this
point in the answer choices and eliminate any that do not contain it. Choice (A) becomes
2(2) = –4 + 8 or 4 = 4, which is true. Choice (B) becomes 2(2) = 4, and (C) becomes 2 =
2(4) – 6 or 2 = 8 – 6. These are also true, but (D) becomes 2 = –2(4), which is false.
Eliminate (D). To sketch the remaining equations, rewrite them in slope-intercept form of
the equation y = mx + b, where m is the slope and b is the y-intercept. Choice (A) becomes
y = − x + 4, (B) becomes y = x, and (C) is already in the right form. Now sketch the