To construct triangle ABC with |AB| = 8 cm, ABC = 90 degrees, and |BC| = 5 cm, follow these steps:
1. Draw a straight line segment AB using the ruler, measuring 8 cm in length.
2. Place the compasses' needle on point A and adjust the pencil end of the compasses so that it measures 5 cm.
3. Keeping the compasses at the same width, draw an arc above and below the line segment AB.
4. Without changing the compasses' width, place the compasses' needle on point B and draw arcs that intersect the previously drawn arcs.
5. Label one of the intersection points as C.
6. Using the ruler, draw a line segment between points B and C.
7. Then, using the ruler, draw a line segment between points C and A.
Triangle ABC is now constructed. Measure the line segment AC to find its length.