Answers:
- convex; pentagon
- concave; octagon
- concave; hexagon
- concave; dodecagon
- convex; triangle
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Step-by-step explanation:
Convex polygons have all of their interior angles between 0 and 180. This applies to polygons 1 and 5.
On the other hand, concave polygons have some interior angles between 180 and 360 known as reflex angles. Visually this means the angle is pushed in to form a mini cave of sorts. This occurs with polygons 2, 3 and 4.
To get the polygon classification, simply count the number of sides and apply the proper name. Figure 1 has 5 sides, so it's a pentagon. Figure 2 has 8 sides so it's an octagon, and so on.