What is the answer to this?

Taking algebra two apex courses and need with these questions

Ade and abc are similar. which best explains why the slope of the line between points a and d is the same as the slope between points a and b?

When constructing a perpendicular line through a point off a line, how can you verify that the lines constructed are perpendicular? check the angles used in the construction with a straightedge to ensure consistency. check the distance along the lines at several places with a compass to ensure they are the same length. check the intersecting lines with the corner of a piece of paper to ensure the lines create 90° angles. check the distance between the lines at several places with a compass to ensure they are equidistant. question 2(multiple choice worth 1 points) (01.03 lc) which of the following steps is included in the construction of a perpendicular line through a point on a line? connect arcs that are above and below the given line with a straightedge. connect arcs that are above the original line with a straightedge. create arcs on either side of a point that is off the given line. create a copied angle by using the first two lines as the original angle.