The slope of the line that passes through the points (x1, y1) and (x2, y2) is computed as follows:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]
a) (0,5) and (-4,2)
[tex]m=\frac{2-5}{-4-0}=\frac{-3}{-4}=\frac{3}{4}[/tex]
b) (4, 5) and (-8, 2)
[tex]m=\frac{2-5}{-8-4}=\frac{-3}{-12}=\frac{1}{4}[/tex]
c) (10, 3) and (18, 7)
[tex]m=\frac{7-3}{18-10}=\frac{4}{8}=\frac{1}{2}[/tex]
Two lines are parallel when they have the same slope, then the correct choice is a
