[icon]/images/ggb/toolbar/mode_circle2.png[/icon]To construct a line perpendicular to a given line through a point that is NOT on the given line, we first create a line segment whose perpendicular bisector will go through the given point.[br]1) Use the Compass tool to create a circle with center P that is large enough to intersect the given line in two places.[br]2) Mark the points where the circle and original line intersect.[br]3) Proceed as in the previous example. Be sure to check your angle using the Angle Measure tool[icon]https://www.geogebra.org/images/ggb/toolbar/mode_angle.png[/icon].