1. Warm Up
Problem of the Day
Lesson Presentation
Lesson Quizzes

2. Warm Up 1. 86 + x = 102 for x = 16 2. 18 + x = 26 for x = 4 yes
Determine whether each value is a solution.
x = 102 for x = 16
x = 26 for x = 4
3. x + 46 = 214 for x = 168
x = 35 for x = 26
yes no
yes
yes

3. Problem of the Day
After Renee used 40 m of string for her kite and gave 5 m to her sister for her wagon, she had 8 m of string left. How much string did she have to start with?
53 m

4. Florida State Standards
FSMA.6.A.3.2 Write [and] solve…one-step linear equations…

5. Vocabulary
inverse operations

6. h + 14 82
The equation h + 14 = 82 can be represented as a balanced scale. h ?
To find the value of h, you need h by itself on one side of the scale.
h + 14 82
To get h by itself, first take away 14 from the left side of the scale. Now the scale is unbalanced. h 68
To rebalance the scale, take away 14 from the other side.

7. Taking away 14 from both sides of the scale is the same as subtracting 14 from both sides of the equation.
h + 14 = 82
–14
–14
h = 68
Inverse operations undo each other. Addition and subtraction are inverse operations. If an equation contains addition, solve it by subtracting from both sides to “undo” the addition.

8. Additional Example 1A: Solving Addition Equations
Solve the equation. Check your answer.
x + 87 = 152
x + 87 = 152
87 is added to x.
– 87
– 87
Subtract 87 from both sides to undo the addition.
x = 65
Check x + 87 = 152
Substitute 65 for x in the equation.
= 152 ?
152 = 152 ? 
65 is the solution.

9. Additional Example 1B: Solving Addition Equations
Solve the equation. Check your answer.
72 = 18 + y
72 = 18 + y
18 is added to y.
–18
–18
Subtract 18 from both sides to undo the addition.
54 = y
Check 72 = 18 + y
Substitute 54 for y in the equation.
72 = ?
72 = 72 ? 
54 is the solution.

10. Solve each equation. Check your answers.
Check It Out : 1A
Solve each equation. Check your answers.
u + 43 = 78
u + 43 = 78
u = 35
- 43 = - 43

11. Check It Out : 1B
Solve each equation. Check your answers.
20 = 6 + n
20 = n
- 6 = -6
14 = n

12. Check It Out : 1C
Solve each equation. Check your answers.
78 + w = 87
78 + w =
w =

13. Check It Out : 2A
For each exercise, write an addition equation. Then solve the equation.
Sandy is thinking of a number. When 33 is added to the number, the sum is equal to 55. What number is Sandy thinking of?
x + 33 = 55;
Sandy is thinking of the number 22.
x = 22;

14. Check It Out : 2B
For each exercise, write an addition equation. Then solve the equation.
SheiKra is a roller coaster at Busch Gardens in Tampa, Florida. You must be 54 inches tall to ride SheiKra. Lisa is 5 inches short of this height requirement. Find the height h of Lisa in inches.
Lisa is 49 inches tall.
h + 5 = 54;
h = 49;

15. Additional Example 2: Social Studies Application
Johnstown, Cooperstown, and Springfield are located in that order in a straight line along a highway. It is 12 miles from Johnstown to Cooperstown and 95 miles from Johnstown to Springfield. Find the distance d between Cooperstown and Springfield.
distance between Johnstown and Springfield
distance between Johnstown and Cooperstown
distance between Cooperstown and Springfield = +
= d
95 = 12 + d
12 is added to d.
–12
–12
Subtract 12 from both sides to undo the addition.
83 = d
It is 83 miles from Cooperstown to Springfield.

16. Check It Out : 2C
For each exercise, write an addition equation. Then solve the equation.
Patterson, Jacobsville, and East Valley are located in that order in a straight line along a highway. It is 17 miles from Patterson to acobsville and 35 miles from Patterson to East Valley. Find the distance d between Jacobsville and East Valley.
17 + d = 35;
d = 18;
It is 18 miles from Jacobsville to East Valley.

17. Check It Out : 2D
For each exercise, write an addition equation. Then solve the equation.
In Olympic archery, competitors use stabilizers to help balance the bow. The main stabilizer is at most 36 inches in length. This is 7 inches more than its minimum length. What is the minimum length of the main stabilizer?
x + 7 = 36;
x = 29;
The minimum length is 29 inches.

18. Lesson Quizzes
Standard Lesson Quiz
Lesson Quiz for Student Response Systems

19. Lesson Quiz
Solve each equation.
1. x + 15 = 72
2. 81 = x + 24
3. x + 22 = 67
4. 93 = x + 14
x = 57
x = 57
x = 45
x = 79
5. Kaitlin is 2 inches taller than Reba. Reba is 54 inches tall. How tall is Kaitlin?
56 inches

20. Lesson Quiz for Student Response Systems
1. Solve the equation x + 26 = 75.
A. x = 39
B. x = 49
C. x = 59
D. x = 101

21. Lesson Quiz for Student Response Systems
2. Solve the equation 71 = y + 47.
A. y = 24
B. y = 28
C. y = 108
D. y = 118

22. Lesson Quiz for Student Response Systems
3. Solve the equation z + 37 = 65.
A. z = 102
B. z = 92
C. z = 38
D. z = 28

23. Lesson Quiz for Student Response Systems
4. Solve the equation 76 = x + 39.
A. x = 27
B. x = 37
C. x = 95
D. x = 115

24. Lesson Quiz for Student Response Systems
5. Steven has 9 more music CDs than Carol. Steven has 25 music CDs. How many music CDs does Carol have?
A. 7 music CDs
B. 9 music CDs
C. 16 music CDs
D. 25 music CDs