Transcript writing Algebraic expression 2 PPx

21st Century Lessons
Writing Algebraic Expressions
Lesson 2
Primary Lesson Designer(s):
Kristie Conners
Sean Moran
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This project is funded by the
American Federation of Teachers.
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21st Century Lessons – Teacher Preparation
Please do the following as you prepare to deliver this lesson:
•
Spend AT LEAST 30 minutes studying the
Lesson Overview, Teacher Notes on each
slide, and accompanying worksheets.
•
Set up your projector and test this PowerPoint file to make
sure all animations, media, etc. work properly.
•
Feel free to customize this file to match the language and
routines in your classroom.
*1st Time Users of 21st Century Lesson:
Click HERE for a detailed description of our project.
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Lesson Overview (1 of 3)
Lesson Objective
Lesson Objective: Students will be able write and read
algebraic and written expressions containing grouping
symbols and less than.
Student Friendly Objective:
Students will be able to write written expressions and
algebraic expressions using ‘grouping symbols’ and ‘less than’.
Lesson Description
This lesson is designed to be implemented following the
previous lesson in this unit. This is the second day where
students will continue their learning in translating written
expression and write algebraic expressions. This lesson
focuses more how to translate grouping symbols and ‘less
than’ in expressions. The class work is designed to really
push the students’ thinking. The next lesson will consist of
evaluating algebraic expressions, which will culminate the
first fours lessons in this unit.
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Lesson Overview (2 of 3)
Lesson Vocabulary
Algebraic Expression: an expression containing at least one variable.
Numerical Expression: an expression containing one or more numbers and
operations.
Written Expression: an expression written with words.
Variable: any letter in the alphabet or symbol that represents a quantity.
Materials
Copies of class work assignment, exit slip, and the homework.
Scaffolding
There are several opportunities throughout the lesson to give student
support. Throughout the launch/explore and in the class work assignment,
support is available to show more details in the lesson if needed. For
example, the list of the order of operations can easily be shown for more
visual learners. Also, proper proof for the class work assignment is also
available at the teacher’s discretion. This will benefit students who are more
visual learners and English Language Learners.
During the class work assignment, teachers have the opportunity to assign a
set of rigorous problems for students who may require the extra challenge.
Enrichment
Online Resources
for Absent
Students
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Tutorial (this video is long, but covers all important content. The last section
will be coved later in the unit.)
http://www.schooltube.com/video/167d4fecea6d4c11b4f5/
Practice: Game- Who Wants To Be A Millionaire
http://www.math-play.com/Algebraic-Expressions-Millionaire/algebraicexpressions-millionaire.html
Practice: Flashcards
http://www.studystack.com/flashcard-301677
Lesson Overview (3 of 3)
Common Core
State Standard
6.EE.2 Write , read, and evaluate expressions in which letters stand for
numbers.
6.EE.2a Write expressions that record operations with numbers and with
letters standing for numbers.
6.EE.2.b Identify parts of an expression using mathematical terms (sum,
term, product, factor, quotient, coefficient); view one or more parts of an
expression as a single entity.
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Before and After
This lesson is the fourth lesson in the unit. This lesson should be presented
following the previous lesson. This lesson is designed implement more
challenging and complex problems involving writing algebraic expressions
and written expressions. This will give students a sound foundation when
asked to evaluate expressions which is part of this unit. The next lesson
will continue to build of the lessons in this unit and will lead into evaluating
algebraic expressions by substitution.
Topic Background
The link below gives a small background on the history of Algebra. This is
also a great opportunity to connect topics covered in social studies with
mathematics.
http://www.ehow.com/video_4977241_who-invented-algebra.html
Warm Up
OBJECTIVE: SWBAT write algebraic expressions using grouping symbols and the
phrase less than. As well as write written expressions from algebraic expressions.
Language Objective: SWBAT speak with a partner about translations between algebra
and English.
1) Sally made 20 more shots than Kevin, k. Write an algebraic
expression to represent how many shots Sally made.
k+20 or 20+k
2) Damon bought a bin of 68 sour candies. He ate c candies. Write
an algebraic expression to represent how many
candies Damon has left.
68 – c
3) What were the key words that helped you write the algebraic
expressions for the problems above?
Agenda
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Agenda:
OBJECTIVE: SWBAT write algebraic expressions using grouping symbols and the
phrase less than. As well as write written expressions from algebraic expressions.
Language Objective: SWBT to translate the meaning ‘sum of’ and ‘difference of’ into
algebraic expressions.
2) Launch
Individual
Marvin’s Math- Whole Class
3) Explore 1
Marvin’s Math Part 1- Whole Class
4) Explore 2
Marvin’s Math Part 2- Whole Class
5) Practice
Class Work- Partners
1) Warm Up
6) Assessment Exit Slip- Individual
Agenda
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Launch- Marvin’s Math
Pick a number, add two, multiply by five.
Let’s get a few volunteers.
What number did you pick? What was your
result?
What did you do first? What did you do second?
Now everyone, let’s use the same number 18.
Agenda
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Explore- Marvin’s Math: Part 1
Pick a number, add two , multiply by five.
What was everyone’s result using 18?
Great! Everyone’s response is 100. This is my
numerical expression using the number 18.
18  2  5
Turn and talk: Is Marvin’s expression correct?
Explain your reasoning.
Agenda
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Explore- Marvin’s Math: Part 1
Turn and talk: Is Marvin’s expression correct?
18  2  5
No! What do we need to do in order to make
this expression equal 100?
Hint
(18  2)  5
Agenda
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Explore- Marvin’s Math: Part 1
Pick a number, add two, multiply by five.
If 10 is picked
If 1 is picked
(18  2) 5
(10  2) 5
(1 2) 5
Our goal is to write this as an



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( x  2)  5
Agenda
Explore- Marvin’s Math: Part 1
( x  2)  5
Our next goal is to write this as an
Let’s break it down into 2 parts.
How do you think we should write ( x  2) as a written
expression?
The word sum
The sum of a number and two.
prompts you to add
Next we combine the two parts.
first.
The sum of a number and two, times five.
Agenda
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Explore- Marvin’s Math: Part 1
OBJECTIVE ALERT
The sum of a number and two, times five.
( x  2)  5
Practice problems
Ex. 1 Write a
for
( x  4)  10
The sum of a number and four, divided by ten
Ex. 2 Write an
for
Four times the difference of a number and six
4  ( x  6)
or
4( x  6)
Agenda
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Explore –Marvin's Math: Part 2
Marvin knows 30 fewer math tricks than his friend.
Here is the
showing the
number of tricks Marvin knows.
30 less than x
a) x  30
b) 30  x
Which is correct?
Lets go back to our basics to figure it out…
Agenda
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Explore –Marvin's Math: Part 2
1. What is 30 less than 50?
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2. What is 30 less than 72?
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3. What is 30 less than 56?
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50 - 30
72 - 30
56 - 30
4. What is 30 less than x?
x - 30
What did you do to get
your answer?
Turn and Talk: When you see
“less than” in a written
expression, what is
important?
Agenda
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Explore –Marvin's Math: Part 2
Marvin knows 30 fewer math tricks than his friend.
Here is the written expression showing the
number of tricks Marvin knows.
30 less than x
a) x  30
b) 30  x
Agenda
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Practice- Class Work
Name__________________
Date____________
Class Work Lesson 4
1) Directions: Write an algebraic expression for each. Let’s do the first one together.
a) five less than three times a number
b) eight less than the quotient of a number
and two
c) nine times the sum of a number and fifteen d) The sum of twice a number and seven
e) one plus the product of a number and five
f) A number less than twenty five
g) The sum of half a number and four
h) seven less than a third of the sum of a
number and two
2) Directions: Write two written expression for each. Use the key vocabulary.
a)
10  h
b)
(d  9)  10
Agenda
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Practice- Class Work
Name__________________
Date____________
Class work lesson 4
1) Directions: Write an algebraic expression for each. Let’s do the first one together.
a) five less than three times a number
3n  5
b) eight less than the quotient of a number
and two
c) nine times the sum of a number and fifteen d) The sum of twice a number and seven
e) one plus the product of a number and five
g) The sum of half a number and four
Important!!!!
f) A number less than twenty five
Identify the
operation(s) by
h) seven less than a third
of the sum
underlining
key of a
number and two
words.
2) Directions: Write two written expression for each. Use the key vocabulary.
a)
10  h
b)
(d  9)  10
Agenda
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Practice- Class Work Summary
Name__________________
Date____________
Class Work Lesson 4
1) Directions: Write an algebraic expression for each.
b) Eight less than the quotient of a number
and two
c) Nine times the sum of a number and fifteen d) The sum of twice a number and seven
f) A number less than twenty five
e) One plus the product of a number and five
h) Seven less than a third of the sum of a
g) The sum of half a number and four
number and two
a) Five less than three times a number
2) Directions: Write two written expression for each. Use the key vocabulary.
a)
10  h
7(n  13)
c
e)
10
g) g (10  h)
c)
b)
(d  9)  10
d)
2 x  12
f)
2  (n  13)
Agenda
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Assessment-Exit Slip
1) Write an algebraic expression for
Three times the sum of a number and eight
3(n  8)
2) Write a written expression for the algebraic expression
using less than.
9n
A number less than nine
3) Write an algebraic expression for
Ten less than the sum of a six and a number
(6  x)  10
Agenda
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