We'll start with point A, not on a line.[br]It takes two points to make a line. I'm showing one (not named) so that we can later move it around.[br][br]We need two points that are on the line that are the same length from A.[br]Can you construct that, using point A and the one point already on the line?[br]Label your intersections B and C.[br][br]Now construct the perpendicular bisector of segment BC [br]by making two circles with radius BC and centers at B and C.[br]Label the intersections of those two circles as D and E.[br][br]Construct line DE.[br]Is point A on line DE? Do a drag test. [br]That is, move all the points you are able. [br]Does your construction stay true? [br] Are the lines always perpendicular? [br]Is segment BC always bisected?[br]What kind of triangle is ABC?[br][br]What can you say about line DE?[br]What can you say about segment BC when it is combined with ANY point on line DE?