Answer:

1. Square

2. Octagon

3. decagon

4. Triangle

5. Nonagon

1) Quadrilateral

2) Octagon

3) decagon

4) triangle

5) nonagon

Explanation:

1) A quadrilateral is a four-sided polygon with four angles. There are many kinds of quadrilaterals. The five most common types are the parallelogram, the rectangle, the square, the trapezoid, and the rhombus

2) An octagon is a polygon made up of 8 sides. It has eight angles.Octagon = Octa + gon where octa means eight and gon means sides.

3) A decagon is a ten-sided polygon or 10-gon.[1] The total sum of the interior angles of a simple decagon is 1440°.

4) A triangle is the simplest polygon, having three sides and three angles. The sum of the three angles of a triangle is equal to 180 degrees

5) A nonagon is a polygon made up of 9 sides and 9 angles. Nonagon = Nona + gon where Nona means nine and gon means sides.