This document provides an overview of subtracting decimals including: 1) Rules for subtracting decimals based on sign including same sign add and different signs take the difference and keep the sign of the higher number 2) Examples of how any subtraction problem can be turned into an addition problem by changing the operation sign 3) A set of practice problems subtracting decimals

1. Pre-Algebra
Lesson 2.11, 2.12
Subtracting Decimals, Part 1 & 2

2. By stating the objectives
for the lesson, retention
increases by 24%!
Did you know that...

3. Rules:
Same sign (+ +, - -)
add numbers together, keep sign
Different signs (+ - , - +)
find difference, take sign of higher number
Review of Adding Decimals:

4. Review of Adding Decimals:

5. Review of last week:

6. What is subtraction?
=
=

7. You can turn any subtraction problem into an
addition problem:
6 - 4
-9 - 13
8 - -3
-14 - (-5)
1.# - #
2. - # - #
3. # - (-#)
4. -# - (-#)

14. Trust Fall
https://www.youtube.com/watch?v=wPOgvzVOQig

16. 1) - 43.4 + x = 15.34 2) x + 19.2 = -19.9
3) x - 98.3 = -12.3 4) x + 55.33 = 23.2