1. Lesson 3-2: Solving Equations by Using Addition and Subtraction

2. Objectives
I can solve one step equations using addition and subtraction

3. Addition Property of Equality
If an equation is true and the same number is added to each side, the resulting equation is true.
Write: If a = b,
Then a + c = b + c

4. Solving Equations
Isolate the variable and simplify

5. Example 1
Solve: h – 12 = -27
h + 0 = -15
h = -15

6. Example 2
Solve: q = -18
q = 3

7. Subtraction Property of Equality
If an equation is true and the same number is subtracted from each side, the resulting equation is true.
Write: If a = b,
Then a – c = b - c

8. Example 3
Solve: k + 63 = 92
k = 29

9. Example 4
Solve: p + 18 = 164
k = 146

10. Story Problems!
The rest of the notes go on the story problem worksheet Mr. Clem provided for you

11. 1) Fourteen more than a number is equal to twenty seven
1) Fourteen more than a number is equal to twenty seven. Write an equation and find the number.

12. Fourteen more than a number is equal to twenty seven
Fourteen more than a number is equal to twenty seven. Write an equation and find the number.
x + 14 = 27

13. Fourteen more than a number is equal to twenty seven
Fourteen more than a number is equal to twenty seven. Write an equation and find the number.
x + 14 = 27

14. Fourteen more than a number is equal to twenty seven
Fourteen more than a number is equal to twenty seven. Write an equation and find the number.
x + 14 = 27
x = 13

15. A number decreased by 10 is 37. Write an equation and find the number.

16. A number decreased by 10 is 37. Write an equation and find the number
A number decreased by 10 is 37. Write an equation and find the number. n – 10 = 37

17. A number decreased by 10 is 37. Write an equation and find the number
A number decreased by 10 is 37. Write an equation and find the number. n – 10 =

18. A number decreased by 10 is 37. Write an equation and find the number
A number decreased by 10 is 37. Write an equation and find the number. n – 10 = n = 47

19. When the Great Wall of China was first built, it was 1,000 miles long
When the Great Wall of China was first built, it was 1,000 miles long. It is now 2,500 miles long. How much wall was added since it was first built? Write an equation and solve.

20. When the Great Wall of China was first built, it was 1,000 miles long
When the Great Wall of China was first built, it was 1,000 miles long. It is now 2,500 miles long. How much wall was added since it was first built? Write an equation and solve. 1,000 + x = 2,500

21. When the Great Wall of China was first built, it was 1,000 miles long
When the Great Wall of China was first built, it was 1,000 miles long. It is now 2,500 miles long. How much wall was added since it was first built? Write an equation and solve. 1,000 + x = 2,500 -1,000 -1,000

22. When the Great Wall of China was first built, it was 1,000 miles long
When the Great Wall of China was first built, it was 1,000 miles long. It is now 2,500 miles long. How much wall was added since it was first built? Write an equation and solve. 1,000 + x = 2,500 -1,000 -1,000 x = 1,500

23. When the Great Wall of China was first built, it was 1,000 miles long
When the Great Wall of China was first built, it was 1,000 miles long. It is now 2,500 miles long. How much wall was added since it was first built? Write an equation and solve. 1,000 + x = 2,500 -1,000 -1,000 x = 1,500 1,500 Miles

24. This past weekend I built a 555 foot tower over two days
This past weekend I built a 555 foot tower over two days. On the second day (Sunday) I added 152 feet. How tall was the tower after one day? Write an equation and solve.

25. This past weekend I built a 555 foot tower over two days
This past weekend I built a 555 foot tower over two days. On the second day (Sunday) I added 152 feet. How tall was the tower after one day? Write an equation and solve. x = 555

26. This past weekend I built a 555 foot tower over two days
This past weekend I built a 555 foot tower over two days. On the second day (Sunday) I added 152 feet. How tall was the tower after one day? Write an equation and solve. x =

27. This past weekend I built a 555 foot tower over two days
This past weekend I built a 555 foot tower over two days. On the second day (Sunday) I added 152 feet. How tall was the tower after one day? Write an equation and solve. x = x = 403

28. This past weekend I built a 555 foot tower over two days
This past weekend I built a 555 foot tower over two days. On the second day (Sunday) I added 152 feet. How tall was the tower after one day? Write an equation and solve. x = x = Feet

29. Homework
Pgs : Evens