1. MODULE I VOCABULARY
PART VI

2. 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.

3. POLYGONS BY NUMBERS
The first figure we’ll discuss today is a triangle.
A triangle is a three-sided polygon.

4. 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.

5. 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.

6. 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.

7. 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.

8. POLYGONS BY NUMBERS Next up is a square.
A square is a polygon with four congruent sides and four right angles.

9. 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.

10. 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.

11. 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.

12. 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.

13. POLYGONS BY NUMBERS
In case you forgot, the distance formula is 𝒙𝟐 −𝒙𝟏 𝟐+(𝒚𝟐 −𝒚𝟏) 2

14. 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

15. 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.

16. POLYGONS BY NUMBERS