How_To_Be_Good_At_Math

36 NUMBERS •^ SQUARE NUMBERS

Square numbers

When we multiply a whole number by itself, the result

is a square number. Square numbers have a special

symbol, a small “2” after the number, like this: 3^2.

A square number is

formed when we

multiply a whole

number by itself.

To show 3^2 , our new square is three

squares wide and three squares deep

• a total of nine squares. This means 9 is
  also a square number.

We can show the squares of numbers as

actual squares. So to show 2^2 , we can

make a square that’s made up of four

smaller squares. So, 4 is a square number.

When we show 4^2 as a square, it’s

made of 4 × 4 small squares, which

makes a total of 16 squares.

This is 5^2 shown as 5 × 5 squares.

There are 25 squares, which is the

same as 5 multiplied by 5. So, the four

square numbers after 1 are 4, 9, 16, and 25.

5 × 5 = 25 or 5² = 25

3 × 3 = 9 or 3² = 9

1 2 3 4 5

6 7 8 9 10

11 12 13 14 15

16 17 18 19 20

21 22 23 24 25

The square measures

2 × 2 small squares

2 × 2 = 4 or 2² = 4

4 × 4 = 16 or 4² = 16

1

4

7

2

5

8

3

6

9

21

65

109

1413

3

7

11

15

4

8

12

16

1

3

2

4

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