Answers:
5. Quadrilateral
6. Rhombus
7. Rectangle
8. Parallelogram
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Explanations:
5. We don't know much about this other than it has 4 sides, so we simply say it is a quadrilateral. Quad = 4, lateral = side
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6. The four sides are the same length as shown by the similar tickmarks. Therefore we have a rhombus. A rhombus is any quadrilateral with four equal sides. A square is a special type of rhombus, though in this case it appears to be a non-square type of rhombus, as the angles are not 90 degrees.
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7. A rectangle has 4 angles that are all 90 degrees. Visually the tiny little square angle marker tells the reader we have a 90 degree angle.
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8. We have a parallelogram here because the opposite sides are the same length. In addition, the opposite angles are the same measure. Through using the SSS congruence rule, we can do a bit of work to show that the alternate interior angles are congruent, leading to the opposite sides being parallel. So in short, the given info here is enough to prove we have opposite sides being parallel which is what makes a parallelogram possible.