Step 1 Using a straightedge, draw an obtuse triangle. Label the vertices as A, B, and C.
Step 2
Draw the perpendicular bisector of side AC.
1. Place the compass point on A, then set the width of the compass so that the distance is slightly longer than half the
length of AC. Then draw an arc that passes through AC and has endpoints above and below point A.
2. Keep the compass setting and place the point of the compass at point C, then draw an arc that passes through
AC and has endpoints above and below point C. The intersection of these ares constructs two points. Label these
points D and E.
3. Using a straightedge, draw DE.
Step 3
Draw the perpendicular bisector of side BC.
1. Place the compass point on B, then set the width of the compass so that the distance is slightly longer than half the
length of BC. Then draw an arc that passes through BC and is above and below point B.
2. Keep the compass setting and place the point of the compass at point C, then draw an arc that passes through
BC and is above and below point B. The intersection of these arcs constructs two points, Label these points F and
G
3. Using a straightedge, draw FG.
Step 4
Mark the intersection of DE and FG. Label this point H. Then place the point of the compass at point H, and set the width
of the compass to one of the vertices of ABC and draw a circle. If you did the construction correctly, this circle intersects
each vertex of the triangle.