UnMessUpable Perpendicular Lines

In the dynamic world of construction, we view good constructions as UnMessUpable. [br]Below you are given two examples of perpendicular lines. But only one of them is UnMessUpable. Which one? (To check, please move the pink points.)[br]Now it is your turn to construct an UnMessUpable pair of perpendicular lines. Your tools are limited, so please follow these steps:[br](i) Click on the "Circle with Center through Point" tool. Construct circle EF, where point E is the center of the circle and the circle goes through point F.(ii) Construct circle FE, where point F is the center of the circle and the circle goes through point E.[br](iii) Click on the "Intersection Two Objects" tool. Click on both circles where they intersect. A point will be placed at the point of intersection. To get a point at the other place of intersection, you will need to click on the other point of intersection.[br](iv) Click on the "Line through Two Points" tool. Construct a line by clicking on the two points of intersection created by the two circles.[br]Congratulations, you should have constructed a pair of UnMessUpable perpendicular lines. But lets check to make sure ...[br]To check your work:[br](1) With the "Arrow" tool activated, move points E and F in your construction to make sure the lines remain perpendicular.[br](2) Click on the button called "Check" to see if your construction matches.

Information: UnMessUpable Perpendicular Lines