Determine whether AB←→ and CD←→ - are parallel, perpendicular, or neither. A (-1, - 4), B (2, 11), C (1, 1), D (4, 10)

Slope of AB

m = (y2 - y1) / (x2 - x1)

m = (11 - (-4)) / (2 - (-1))

m = (11 + 4) / (2 + 1)

m = 15/3

m = 5

The slope of line AB is 5

Slope of CD

m = (y2 - y1) / (x2 - x1)

m = (10 - 1) / (4 - 1)

m = 9/3

m = 3

The slope of CD is 3

Since the two slopes are not equal, this means the lines are not parallel.

Since (slope of AB) * (slope of CD) = 5*3 = 15 is not equal to - 1, this means the lines are not perpendicular

Answer: Neither (not parallel; not perpendicular)