Page 84 - Algebra 1

L E S S O N Calculating and Comparing Square Roots 13
Warm Up
New Concepts
1. Vocabulary The number that tells how many times the base of a power is
(3)
used as a factor is called the (variable, exponent). Simplify each expression.
2. −3 + (−4) − (−8) (10)
4. a3 · x4 · x8 · a4 · z4 (3)
3. [−(−4)3] (11)
5. (-_2 )÷ (-_3 ) (11) 6 8
Math Reasoning
Formulate What is the inverse of x2 ?
Example
1
Online Connection www.SaxonMathResources.com
A perfect square is a number that is the square of an integer. The product of an integer and itself is a perfect square.
22 = 32 =
A square root is indicated by a radical symbol √ . A radicand is the number
or expression under a radical symbol.
√ 5 0 2 √ 7
50 is the radicand. 7 is the radicand.
The square root of x, written √ x, is the number whose square is x.
42 = 16 √ 16 = 4
A square number can only end with the digits: zero, one, four, five, six, and nine. However, not all numbers ending in these digits will be perfect squares.
Finding Square Roots of Perfect Squares
a. Is the radicand in √ 50 a perfect square? Explain.
SOLUTION
50 is not a perfect square. There is no integer multiplied by itself that equals 50.
b. Is the radicand in √ 64 a perfect square? Explain. SOLUTION
64 is a perfect square; 8 · 8 = 82 = 64. The product of an integer and itself is a perfect square.
Lesson 13 69