Square and Cube Roots

Square and Cube Roots

Unit 1

Square Roots

What is a square?

How to Square A Number: 

To square a number: multiply it by itself.

Example: What is 3 squared?

3 Squared= 3 × 3 = 9

 "Squared" is often written as a little 2 in the upper right corner of the number (the little 2 says the number appears twice in multiplying)

Open Ended

What Operation are you using when you square a number?

Open Ended

What is 14² actually telling you to do?

Open Ended

Can you take the square root

Multiple Choice

Can we take the square root of a negative number?

• yes

• no

Multiple Choice

How many answers do can you get when you find the square root of a number?

• 1

• 2

• 3

• 4

• None of the Above

Open Ended

What is the square root? $\sqrt{121}$  

Multiple Choice

Does the square root of $\sqrt{121}$ have one or two solutions? 

• 1

• 2

Open Ended

How do I know when a square roots has two solutions?

Steps to approximate square roots

• Locate the closest perfect square root (one smaller, one bigger)

• Decide which one is actually closer to the desired radicand

• Approximate its value if it was on a number line.

Multiple Select

Without using a calculator, put the numbers in order.

 $\sqrt{72}$ , 9 , 7, 8

•  $7,\ 8,\ \sqrt{72},\ 9$  

•  $7,\ \sqrt{72},\ 8\ ,\ 9$  

•  $\sqrt{72},\ 7\ ,\ 8\ ,\ 9$  

•  $7,\ 8,\ 9,\ \sqrt{72}$  

Cube Roots

Open Ended

What is  $8^3$ ?

Open Ended

What are the differences between a square root and a cube root?

Steps to approximate cube roots

• Locate the closest perfect cube root (one smaller, one bigger)

• Decide which one is actually closer to the desired radicand

• Approximate its value if it was on a number line.

Equations with Square and Cube Roots

Equations with Square Roots

What is this asking you to do?

Multiple Select

Find the solutions for the equation. Select all that apply

• $g\ =\ \sqrt{12}$

• $g\ =\ -\sqrt{12}$

• 14

• -14

• None of the above

Equations with Cube Roots

What is this asking for you to do?

Multiple Select

Find the solution for the equation. Select all that apply

• y = 3

• y = -3

• y = 9

• y = -9

• None of the above

Decimals and Fractions Square and Cube Roots

They are no different

The answer is 3/4

Decimals you can do the same thing as approximating from above

or you can use this trick to help you.

Open Ended

 $\sqrt{0.64}$  

Open Ended

 $\sqrt{1.96}$  

Poll

Stoplight Review: How do you feel about today's lesson?

• Green Light - Full Speed Ahead

• Yellow Light - I'll get there slowly with practice

• Red Light - I don't know where you are at?