1. Perfect Squares & Estimating Square Roots
Unit 1
Perfect Squares & Estimating Square Roots

2. On the next slide is a list of perfect squares.

3. 1= 1
8= 64
15= 225
2= 4
9= 81
3= 9
10= 100
4= 16
11= 121
5= 25
12= 144
6= 36
13= 169
7= 49
14= 196

4. What is a Square Root?
A square root is a number that, when multiplied by itself, equals a specific number.
4 is the square root of 16 because
4 × 4 = 16
Every number has 2 square roots:
Principal Root – positive square root
Negative Root – negative square root

5. What is a Perfect Square?
A perfect square is a number that has an integer for its square root.
16 is a perfect square because its square root is an integer ( 16 =4)
17 is not a perfect square because its square root is a decimal.4 × 4 = 16

6. If you don’t have a perfect square, you can estimate the square root.
4 examples are shown on the next slide.

7. 12 22 9 16 16 25
3 < < 4
4 < < 5
12 ≈3
22 ≈5
200 63 49 64
196
225
7 < < 8
14 < < 15
63 ≈8
200 ≈14