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Algebra
                                                                           Lesson 5




                                                                             Tennessee
                                                                           Adult Education




This curriculum was written with funding of the Tennessee Department of Labor and Workforce Development and may not be reproduced in any way without written permission. ©
What is Algebra?
A clown was carrying a handful of balloons.
Along came the wind and blew 8 away, leaving
him only with 9. How many did he start with?
             Algebra takes real life problems and puts
             them into math so we can solve them.


                            x-8 = 9
                The goal in Algebra is to find out the
                             unknown!
A scale has 20 pennies on one side . On the other side is 6 pennies
and an unknown amount of pennies. Both sides equal the same
weight.




      20 = 6 + x



                                      20               6 pennies
                                      pennies          + ? pennies
x-8 = 9
 +8 +8
x = 17



x-8       9
What is Algebra?
A clown had 17 balloons. Along came the wind
and blew 8 away, leaving him only with 9.



              The goal in Algebra is
                 to find out the
                   unknown!
-Different signs subtract numbers

 -Always keep the sign of the larger number
       when subtracting and adding



-3 + 7 = 4
- - - +++ +++ +
-2 + 9 = 7

- - +++ +++ +++
-4 + 2 = -2

- - - - ++
-7 + 5 =    -2

- - - - - - - +++ ++
-3 + 16 = 13

---     +++ +
+++ +++ +++ +++
-if both negatives, add together
        - keep the negative sign




-5 + -5 = -10
 --- --
 --- --
-8 + -4 = -12

--- --- --
--- -
In math 2 negatives (-)(-)

   equal a positive (+)
-4 – (-3) =
 -4 + 3 = -1
--- -
+++
-8 – (-4) =
 -8 + 4 = -4
--- --- --
+++ +
-6 – (-8) =
 -6 + 8 = 2
--- ---
+++ +++ ++
-2 – (-7) =
 -2 + 7 = 5
--
+++ +++ +
-9 – (-3) =
 -9 + 3 = -6
--- --- ---
+++ +++
Rule               Add/Subtract
Same signs -              1+3= 4
add numbers
                         -1 - 3 = -4

Different signs -        -3 + 4 = 1
subtract numbers
                          4–3=1
       Keep sign of the largest number

         Rule               Add/Subtract

++                     4 + (-2) =
--                     4–2=2
+-                     -3 – (-4) =
-+                     -3 + 4 = 1
Guided Practice

1.   +8 – 14 = ______      7.   5 x -3 = ______
2. -2 + 11 = ______        8. -6 x 2 = ______

3. -33 - 22 = ______       9. -4 x -8 = ______

4. (-7) + (-3) = ______    10. 42 ÷ -7= ______

5. (-10) + (16) = ______   11. -3 x -9 = ______

6. -4 – (-4) = ______      12. -20 ÷-2 = ______
Order of Operations
     Please Excuse My Dear Aunt Sally

1.   Parenthesis           (4-2)
2.   Exponent              4³
3.   Multiply              4(3) or 4x3
4.   Divide                4÷2 or 4/2
5.   Add                   4+2
6.   Subtract              4-2
(6-4)² - 2 =

(2) ²- 2 =

4–2=

2
(6x2)(8÷2) ² =

(12)(4) ² =

(12)(16) =

192
2(3 + 2 x 6 -1)² =

2(3 + 12 – 1) ² =

2(15 – 1) ² =

2(14) ² =

2(196) =

392
3x4+6÷2+5-1

12 + 6 ÷ 2 + 5 – 1

12 + 3 + 5 – 1

15 + 5 – 1

20 – 1

19
Key Terms
•   product           multiply
•   squared           times itself
•   sum               add
•   difference        subtract
•   half              divide by 2 or ½
•   quotient          divide
•   decreased         subtract
Guided Practice
six more than the square of four is twenty two=
                   4² + 6 = 22

                    5x – 1 = 7
one less than five times a number equals seven

the quotient of a twelve and four plus a number
                    12 ÷ 4 + n
Algebra Rules

1. What you do to one side you must do to the other. This keeps
   them equal.

2. You must get the variable by itself to find out what number
   value it equals.
Guided Practice
-4 = x + 2              ½ n -4 = 9-2
-2      -2              ½ n -4 = 7
 x = -6                     +4 +4
                        ½ n = 11
 3 + 2n = 43            2( ½ n) = 11(2)
-3         -3           n = 22
2n = 40
 2    2
n = 20
Substitution
– you put the number where the letter was

                  what is:
                   x-2

                   if x = 6

                   6 -2 = 4
Guided Practice

3(n) – 2(4) + 16 / x   if x = 4
3(4) – 2(4) + 16 / 4
12 – 8 + 16 / 4
12 – 8 + 4
12 – 12
0
Guided Practice

b³c + bc + 2b²           if b = 3; c = 4

(3) ³(4) + (3)(4) + 2(3) ²

9(4) + (3)(4) + 2(9)

36 + 12 + 18

66
Key Terms
• expression
  – a way to represent spoken information about an
    unknown number:
  “a number plus 3” = n + 3
• equation
  – shows that two quantities are equal
• inequality
  – uses symbols < and > to show “greater than” and
    “less than”
6 algebra

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6 algebra

  • 1. Algebra Lesson 5 Tennessee Adult Education This curriculum was written with funding of the Tennessee Department of Labor and Workforce Development and may not be reproduced in any way without written permission. ©
  • 2. What is Algebra? A clown was carrying a handful of balloons. Along came the wind and blew 8 away, leaving him only with 9. How many did he start with? Algebra takes real life problems and puts them into math so we can solve them. x-8 = 9 The goal in Algebra is to find out the unknown!
  • 3. A scale has 20 pennies on one side . On the other side is 6 pennies and an unknown amount of pennies. Both sides equal the same weight. 20 = 6 + x 20 6 pennies pennies + ? pennies
  • 4. x-8 = 9 +8 +8 x = 17 x-8 9
  • 5. What is Algebra? A clown had 17 balloons. Along came the wind and blew 8 away, leaving him only with 9. The goal in Algebra is to find out the unknown!
  • 6. -Different signs subtract numbers -Always keep the sign of the larger number when subtracting and adding -3 + 7 = 4 - - - +++ +++ +
  • 7. -2 + 9 = 7 - - +++ +++ +++
  • 8. -4 + 2 = -2 - - - - ++
  • 9. -7 + 5 = -2 - - - - - - - +++ ++
  • 10. -3 + 16 = 13 --- +++ + +++ +++ +++ +++
  • 11. -if both negatives, add together - keep the negative sign -5 + -5 = -10 --- -- --- --
  • 12. -8 + -4 = -12 --- --- -- --- -
  • 13. In math 2 negatives (-)(-) equal a positive (+)
  • 14. -4 – (-3) = -4 + 3 = -1 --- - +++
  • 15. -8 – (-4) = -8 + 4 = -4 --- --- -- +++ +
  • 16. -6 – (-8) = -6 + 8 = 2 --- --- +++ +++ ++
  • 17. -2 – (-7) = -2 + 7 = 5 -- +++ +++ +
  • 18. -9 – (-3) = -9 + 3 = -6 --- --- --- +++ +++
  • 19. Rule Add/Subtract Same signs - 1+3= 4 add numbers -1 - 3 = -4 Different signs - -3 + 4 = 1 subtract numbers 4–3=1 Keep sign of the largest number Rule Add/Subtract ++ 4 + (-2) = -- 4–2=2 +- -3 – (-4) = -+ -3 + 4 = 1
  • 20. Guided Practice 1. +8 – 14 = ______ 7. 5 x -3 = ______ 2. -2 + 11 = ______ 8. -6 x 2 = ______ 3. -33 - 22 = ______ 9. -4 x -8 = ______ 4. (-7) + (-3) = ______ 10. 42 ÷ -7= ______ 5. (-10) + (16) = ______ 11. -3 x -9 = ______ 6. -4 – (-4) = ______ 12. -20 ÷-2 = ______
  • 21. Order of Operations Please Excuse My Dear Aunt Sally 1. Parenthesis (4-2) 2. Exponent 4³ 3. Multiply 4(3) or 4x3 4. Divide 4÷2 or 4/2 5. Add 4+2 6. Subtract 4-2
  • 22. (6-4)² - 2 = (2) ²- 2 = 4–2= 2
  • 23. (6x2)(8÷2) ² = (12)(4) ² = (12)(16) = 192
  • 24. 2(3 + 2 x 6 -1)² = 2(3 + 12 – 1) ² = 2(15 – 1) ² = 2(14) ² = 2(196) = 392
  • 25. 3x4+6÷2+5-1 12 + 6 ÷ 2 + 5 – 1 12 + 3 + 5 – 1 15 + 5 – 1 20 – 1 19
  • 26. Key Terms • product multiply • squared times itself • sum add • difference subtract • half divide by 2 or ½ • quotient divide • decreased subtract
  • 27. Guided Practice six more than the square of four is twenty two= 4² + 6 = 22 5x – 1 = 7 one less than five times a number equals seven the quotient of a twelve and four plus a number 12 ÷ 4 + n
  • 28. Algebra Rules 1. What you do to one side you must do to the other. This keeps them equal. 2. You must get the variable by itself to find out what number value it equals.
  • 29. Guided Practice -4 = x + 2 ½ n -4 = 9-2 -2 -2 ½ n -4 = 7 x = -6 +4 +4 ½ n = 11 3 + 2n = 43 2( ½ n) = 11(2) -3 -3 n = 22 2n = 40 2 2 n = 20
  • 30. Substitution – you put the number where the letter was what is: x-2 if x = 6 6 -2 = 4
  • 31. Guided Practice 3(n) – 2(4) + 16 / x if x = 4 3(4) – 2(4) + 16 / 4 12 – 8 + 16 / 4 12 – 8 + 4 12 – 12 0
  • 32. Guided Practice b³c + bc + 2b² if b = 3; c = 4 (3) ³(4) + (3)(4) + 2(3) ² 9(4) + (3)(4) + 2(9) 36 + 12 + 18 66
  • 33. Key Terms • expression – a way to represent spoken information about an unknown number: “a number plus 3” = n + 3 • equation – shows that two quantities are equal • inequality – uses symbols < and > to show “greater than” and “less than”