• Home
  • Textbooks
  • Understanding Elementary Algebra with Geometry
  • Radical Expressions and Equations

Understanding Elementary Algebra with Geometry

Lewis Hirsch, Arthur Goodman

Chapter 10

Radical Expressions and Equations - all with Video Answers

Educators


Section 1

Definitions and Basic Notation

00:11

Problem 1

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{4}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 2

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{9}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 3

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$-\sqrt{4}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 4

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$-\sqrt{9}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:10

Problem 5

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{-4}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:10

Problem 6

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{-9}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 7

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{25}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:12

Problem 8

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{49}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:13

Problem 9

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$-\sqrt{100}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:06

Problem 10

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$-\sqrt{36}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 11

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{64}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:06

Problem 12

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{81}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 13

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{121}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:11

Problem 14

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{144}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:10

Problem 15

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{169}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:11

Problem 16

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{196}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 17

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{225}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:10

Problem 18

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{256}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 19

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{289}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:10

Problem 20

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{324}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 21

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{361}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 22

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{400}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 23

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{3} \sqrt{3}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:06

Problem 24

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{10} \sqrt{10}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 25

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{29} \sqrt{29}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 26

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{67} \sqrt{67}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 27

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{11})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 28

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{5})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:11

Problem 29

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{33})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:11

Problem 30

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{41})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 31

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{x} \sqrt{x}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 32

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{x})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:25

Problem 33

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{7})^{4}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:27

Problem 34

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{3})^{6}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:28

Problem 35

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{7})^{5}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:28

Problem 35

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{7})^{5}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:34

Problem 36

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{3})^{7}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:15

Problem 37

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{25-9}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:14

Problem 38

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{100}-\sqrt{36}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:13

Problem 39

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{25}-\sqrt{9}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:17

Problem 40

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$\sqrt{100-36}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:17

Problem 41

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{25}-\sqrt{9})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:13

Problem 42

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{100-36})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:13

Problem 43

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{25-9})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:21

Problem 44

Evaluate or simplify each expression. (Assume $x \geq 0 .)$
$$(\sqrt{100}-\sqrt{36})^{2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:24

Problem 45

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{425}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:08

Problem 46

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{983}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 47

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{637}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:09

Problem 48

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{730}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 49

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{73.6}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 50

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{58.9}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 51

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{2.09}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:06

Problem 52

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{7.85}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 53

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{0.037}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:07

Problem 54

Use a calculator to find the following square roots. Round off your answers to the nearest hundredth.
$$\sqrt{0.00049}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:17

Problem 55

Use a calculator to give decimal approximations rounded to one, two, and three places.
$$\sqrt{17}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:15

Problem 56

Use a calculator to give decimal approximations rounded to one, two, and three places.
$$\sqrt{23}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:19

Problem 57

Use a calculator to give decimal approximations rounded to one, two, and three places.
$$\sqrt{110}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:13

Problem 58

Use a calculator to give decimal approximations rounded to one, two, and three places.
$$\sqrt{260}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:40

Problem 59

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{73}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:13

Problem 60

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{115}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:38

Problem 61

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{217}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:17

Problem 62

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{59}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:27

Problem 63

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{673}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:35

Problem 64

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{318}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:26

Problem 65

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{285}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:27

Problem 66

Estimate the given square root between two consecutive integers without using a calculator, then use a calculator to find the square root rounded to two decimal places to confirm your estimate.
$$\sqrt{872}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:23

Problem 67

Determining whether a number is a perfect square is not as hard as it might at first seem. For instance, suppose we wanted to know whether the number 648 is a perfect square. Do you see why the square root of 648 must be between 20 and $30 ?$ Can you think of an easy way to check whether 648 can possibly be a perfect square? [Hint: Think about the possible final digit a perfect square can have.] Is 648 a perfect square?

Amy Jiang
Amy Jiang
Numerade Educator
00:15

Problem 68

Use the result of Exercise 67 to check whether 841 can possibly be a perfect square. Is it?

Amy Jiang
Amy Jiang
Numerade Educator
00:30

Problem 69

Discuss the correctness of the following steps:
$$\begin{aligned}
\sqrt{2} & \underline{z} \sqrt{1+1} \\
& \stackrel{?}{=} \sqrt{1}+\sqrt{1} \\
& \stackrel{?}{=} 1+1 \\
& \stackrel{\underline{2}}{=} 2
\end{aligned}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:10

Problem 70

Describe the following statement in words:
$$\sqrt{a} \sqrt{a}=a$$

Amy Jiang
Amy Jiang
Numerade Educator
00:19

Problem 71

What is the difference between saying "a square root of 9 " and writing $\sqrt{9} ?$

Amy Jiang
Amy Jiang
Numerade Educator
00:21

Problem 72

Perform the indicated operations and simplify.
$$\frac{x^{2}-6 x}{x^{2}} \cdot \frac{2 x}{x^{2}-12 x+36}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:51

Problem 73

Perform the indicated operations and simplify.
$$\frac{y^{2}+2 y}{y^{2}-4} \div \frac{y^{2}}{y^{2}-6 y+8}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:26

Problem 74

Perform the indicated operations and simplify.
$$\frac{3}{2 x}+\frac{5}{x+2}$$

Amy Jiang
Amy Jiang
Numerade Educator
00:21

Problem 75

Perform the indicated operations and simplify.
$$\text { Solve for } x, \quad \frac{6}{x-6}=\frac{2}{x-2}$$

Amy Jiang
Amy Jiang
Numerade Educator
02:30

Problem 76

Solve the following problems algebraically. Be sure to label what the variable represents.
A hardware store sells 40 lightbulbs. Some were regular bulbs selling for $75 \notin$ each, and the rest were long-life bulbs selling for $89 \notin$ each. If $\$ 31.68$ was collected for the bulbs, how many of each type were sold?

James Kiss
James Kiss
Numerade Educator
04:42

Problem 77

Solve the following problems algebraically. Be sure to label what the variable represents.
Xavier made three investments at $6.5 \%, 7.6 \%,$ and $9.2 \% .$ The amount invested at
$7.6 \%$ is $\$ 1000$ less than the amount invested at $9.2 \%,$ and the amount invested at
$6.5 \%$ is twice the amount invested at $7.6 \% .$ If the annual income from the three investments is $\$ 837,$ how much is invested altogether?

James Kiss
James Kiss
Numerade Educator