CSOLVING MULTI-

STEP EQUATIONSCommon Core Objective 8.EE.7

C

I, THE STUDENT, WILL BE ABLE TO:

1. SOLVE EQUATIONS WITH LINEAR EXPRESSIONS WITH ONE SOLUTION, INFINITELY MANY SOLUTIONS OR NO SOLUTIONS (8.EE.7)

2. GIVE EXAMPLES OF AND IDENTIFY EQUATIONS AS HAVING ONE SOLUTION, INFINITELY MANY SOLUTIONS OR NO SOLUTIONS (8.EE.7)

OBJECTIVE

WARM UP – Thursday, October 16th Amy and Ben are trying to decide when the following equation is true:

They decided to compare their work.

Amy: Ben: If you take a number away from 5 the

so x = 6 – 5 = 1answer will be less than 5, so it’s

so it is true when x = 1 never true.

Are Amy and Ben correct? If not, where have they gone wrong?

Amy: ________________________________________________________________

Ben: _________________________________________________________________

What is your answer to the question? _______________________________________

______________________________________________________________________

True or False?

Can you give me a value for x that makes this equation false?Show the calculations that explain your answer by writing on your desk with a dry erase marker.

True or False?

Can you give me a value for x that makes this equation true?Show the calculations that explain your answer by writing on your desk with a dry erase marker.

How many different values of x make the equation true?

Cheryl: Stacey:

(not 3)

This means and this (this doesn’t work) always has to

be true. To

make 2, must be because (this doesn’t work)

x can’t be any other value.There is only one value for x that makesthe equation true.

Collaborative Activity: Always, Sometimes, or Never True? (30 Minutes)

•You will work in groups of three or four.

•Each group should have a Card Set: Equations, a pair of scissors, a large sheet of paper, a marker, and a glue stick. You will also need a pencil to use when writing your explanations.

•You will be considering a number of equations in the same way we have been solving equations. In your groups, you will produce a poster that will show each equation classified according to whether it is always, sometimes, or never true.

Always, Sometimes, or Never True?•You will need to divide your sheet of paper into three columns and head separate columns with the words:

•What does always true mean?

•What does never true mean?

•How many examples does it take to prove that an equation is sometimes true?

Always True Sometimes True

Never True

How will you work together?

1. One partner, selects an equation, cuts it out and places it in one of the columns, explaining why you choose to put it there.

2. If you think the statement is sometimes true, give values of for which it is true. If you think the equation is always true or never true, explain how you can be sure this is the case.

3. Partners should challenge the explanation if they disagree OR describe it in their own words if they agree.

4. Once you agree, stick the equation on the poster and write an explanation on the poster in pencil next to the card.

5. Swap roles and continue to take turns until all equations are placed.

Sharing Posters (10 minutes)

1.Move to another table and look at their poster.

2.If you disagree with where an equation has been placed, put a circle around the equation and write in pen:•Why you disagree•Which column you think the equation needs moving to.•Why you think the equation belongs there.

3.Circle your comments and write your initials next to them.

Let’s Summarize (15 minutes)

Give me an equation that is always true/sometimes true/never true.

Why did you put this equation in this column?Did anyone put this equation in a different column?

TICKET OUT!

Using your technology, you will answer 3 questions in google drive.

Go to my wiki page and click on the link under today’s PowerPoint/date.

Please only respond once to the questions.

Your homework tonight is the half sheet titled: When are the equations true?

Warm Up – Friday, October 17th

Solve the following equations: