3.8 Findin
g and Es
timating S
quare Ro
ots
Vocab
square root side length of a square,
ie side length of a square = square root of the area of the square
the symbol,
square root
+
16
= 4 or -4
principle square root 16 is 4, the positive integer
negative square root -
-
16 is -4, the negative integer
radical sign radicand the number or expression under the radical sign
121
note - + indicates both positive and negative
, represents
Simplify each expression:
Thinking back . . .
Explain the difference between a rational and an irrational number.
Identify each expression as rational of irrational:
perfect squares squares whose side lengths are whole numbers
1
2
3
4
5
1
4
9
16
25
6
7
8
9
10
36
49
64
81
100
11
12
13
14
15
121
144
169
196
225
16
17
18
19
20
256
289
324
389
400
Between which two consecutive whole numbers do each of the following
square roots fall?
27.9
114.4
311
234.5
404.04
3.8 Quick Check
Grade: 8th
Subject: Algebra
1 Simplify
√49
2 Simplify
-√196
3
The number below belongs to
which subset of the real number
system?
√294
A
Rational
B
Irrational
4 The number below belongs to which subset
of the real number system?
√169
A
Rational
B
Irrational
- Between which
two consecutive
integers does
-√105
fall between?
p178: 1-48even