Diagonals

In geometry, a diagonal is a line segment that connects two non-adjacent vertices of a polygon. The term "diagonal" is commonly used to refer to the line segments that form an "X" shape within a polygon.

The number of diagonals in a polygon can be determined using the formula:

number of diagonals = n(n-3)/2

Where n represents the number of sides in the polygon. For example, a quadrilateral (4-sided polygon) has 2 diagonals, a pentagon (5-sided polygon) has 5 diagonals, and so on.

Diagonals have several properties and applications in geometry. For instance, in a rectangle or a square, the diagonals are congruent and bisect each other. In a regular polygon, the number of diagonals can be used to calculate the total number of line segments that can be drawn connecting the vertices.

Understanding diagonals is important in geometry as it helps in analyzing the internal structure of polygons and determining various geometric properties.

Overall, diagonals play a significant role in the study of polygons and can be a useful concept in solving geometric problems and proofs.

◂Math Worksheets and Study Guides Kindergarten. Counting 1-100

The resources above cover the following skills:

Counting and Cardinality

Know number names and the count sequence.

Count to 100 by ones and by tens. [K-CC1]

Count forward beginning from a given number within the known sequence (instead of having to begin at 1). [K-CC2]

Count to tell the number of objects.

Understand the relationship between numbers and quantities; connect counting to cardinality. [K-CC4]

When counting objects, say the number names in the standard order, pairing each object with one and only one number name and each number name with one and only one object. [K-CC4a]

Understand that the last number name said tells the number of objects counted. The number of objects is the same regardless of their arrangement or the order in which they were counted. [K-CC4b]

Understand that each successive number name refers to a quantity that is one larger. [K-CC4c]

Count to answer “how many?” questions about as many as 20 things arranged in a line, a rectangular array, or a circle, or as many as 10 things in a scattered configuration; given a number from 1-20, count out that many objects. [K-CC5]

Compare numbers.

Compare two numbers between 1 and 10 presented as written numerals. [K-CC7]

Diagonals

[Diagonals] Related Worksheets and Study Guides:

◂Math Worksheets and Study Guides Kindergarten. Counting 1-100

The resources above cover the following skills: