1. Squares and square roots
Objective:
Find squares of numbers and square roots of perfect squares.

2. The Area of the square at the right is 5 x 5 or 25 square units.
The product of a number and itself is the square of a number. So, the square of 5 is 25.
Square also means to the second power, so 52 = 5 x 5 = 25
Examples: 1) Find the square of 3.
2) Find the square of 15.

3. Perfect squares:
Numbers like 9, 16, and 25 are called square numbers or perfect squares because they are squares of whole numbers.
For Example: 9 = 3 x 3
16 = 4 x 4
25 = 5 x 5

4. Square roots:
The factors multiplied to form a perfect square are called square roots.
A radical sign √ is the symbol used to indicate a square root of a number.
A square root of a number is one of its two equal factors.
For example: 4 x 4 = 16, so the √16 = 4
Examples: Find √81
Find √225

5. Homework: Squares and square roots (You must show work in #´s 5,6,7,8,14,15,16. )
Find the square of each number. 4 1 7 11 16 20 18 34