Step-by-step explanation:
All of these are done the same way.
1. Set your compass to a distance slightly longer than the distance from the point to the line you want the perpendicular to.
2. Using the point as a center, draw an arc that intersects the line in 2 places. Consider those points to be "P" and "Q".
3. You can leave the compass as is, or set it to any other distance longer than half the distance between P and Q. Using this radius, and using P and Q as centers, draw intersecting arcs on the other side of the line from the original point. Consider the intersection of those arcs to be point "R".
4. A line through the original point and point R will be perpendicular to the line, as you want.
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In problem 1, the point and line are obvious.
In problem 2, the point is the vertex opposite the line of interest. (There will be 3 similar constructions.)