MODULE I VOCABULARYPART VI

POLYGONS BY NUMBERS

• Today, we will be discussing the last few of our vocabulary words.

• Most of these are words you have heard before, but today, we’ll be talking about them in a bit of a different way.

POLYGONS BY NUMBERS

• The first figure we’ll discuss today is a triangle.• A triangle is a three-sided polygon.

POLYGONS BY NUMBERS

• There are three names for triangles based on their angles.

• They are obtuse, acute and right.• There are three names for triangles based on

their sides.• They are equilateral, isosceles, and scalene.

POLYGONS BY NUMBERS

• Obtuse triangles have one angle that is larger than 90⁰.

• Acute triangles have only angles that are smaller than 90⁰.

• Right triangles have one angle which is exactly 90⁰.

POLYGONS BY NUMBERS

• Equilateral triangles have all sides of the same length.

• Isosceles triangles have two sides of the same length.

• Scalene triangles have no sides of the same length.

POLYGONS BY NUMBERS

• The perimeter of a triangle is calculated by adding all the side lengths together.

• The area is found by ½ base x height. • Most often, for now, we’ll be working with

right triangles.

POLYGONS BY NUMBERS

• Next up is a square.• A square is a polygon with four congruent

sides and four right angles.

POLYGONS BY NUMBERS

• The perimeter of a square is calculated by adding all the side lengths together.

• The area is found by base x height.

POLYGONS BY NUMBERS

• Next is a rectangle.• A rectangle is simply a figure with four right

angles.• The perimeter of a rectangle is calculated by

adding all the side lengths together.• The area is found by base x height.

POLYGONS BY NUMBERS

• A polygon is a two-dimensional, closed figure formed by three or more lines.

• All of the figures we have discussed thus far are polygons.

POLYGONS BY NUMBERS

• The perimeter is the distance around the outside of a polygon.

• We can find this on polygons that are on the coordinate plane.

• To do so, we use the distance formula.

POLYGONS BY NUMBERS

• In case you forgot, the distance formula is 2

POLYGONS BY NUMBERS

• Lastly, a theorem is a math statement proven to be true.

• We will be using theorems in our study of proofs.

• A proof is a stepwise series of reasoning leading us from a given statement to desired conclusion

POLYGONS BY NUMBERS

• For instance, a type of proof you may be asked to do is to prove that a certain figure, is indeed that figure.

• You can do so by proving their properties.

POLYGONS BY NUMBERS