6th Grade Math Textbook, Progress

To complete the analogy, first draw some

polygons and then count the number of diagonals.

Draw and count the number of

diagonals in a hexagon.

Visualize yourself in the problem above as you

reread it. List the facts and the question.

Facts: a polygon with 2 diagonals

a polygon with 9 diagonals

Question:Which two polygons should she choose?

Helen has to choose two different polygons to complete

this analogy. Which two polygons should she choose?

2 diagonals are to a? as 9 diagonals are to a ?.

Problem-Solving Strategy:

Logical Reasoning

10-19

A square is a quadrilateral.

A square has 2 diagonals.

All quadrilaterals have 2 diagonals.

Look at the pattern in the table.

What number should be added to 5 to find

the number of diagonals in a hexagon? 4

5 
 4 9 number of diagonals in a hexagon

So 2 diagonals are to a quadrilateral

as 9 diagonals are to a hexagon.

 2 
 3 
?

4

1

5

8

2

6

9

3

7

Polygon

Number of

Diagonals

?

0 2 5?

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