Answer: 8 pairs of perpendicular lines
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The 8 perpendicular pairs of lines are:
- AB and BC
- BC and CD
- CD and DE
- DE and EF
- EF and FG
- FG and GH
- GH and HA
- HA and AB
I started with AB and worked counterclockwise around the figure so that I could methodically list each pair of perpendicular lines. Perpendicular lines always form a 90 degree angle. While the square angle markers aren't there, I'm assuming your teacher meant to put them in.
Alternatively, you can count the number of right angles and you'll also get 8 as the answer.
