Meet Mrs. Rowe

Background

19 year math teacher with Gladbrook Reinbeck schools. Loves to work with students and see their new learning! Wants all students to be successful.

Mrs. Rowe's "Theorem"

Working with Subtracting Integers.

To subtract with negatives is the same thing as adding the inverse. Mrs. Rowe teaches the students KFC to help them remember.


What does KFC mean?

K Keep it

F Flip to add

C Change the sign


When students apply the KFC rule, they can easily work with subtracting both positive and negative numbers. Let's take a look:

-3 - 5 is the same as -3 (Keep it) + (Flip to add) -5 (Change the sign). So that's -3 + -5. When signs are the same, you add and keep signs. Answer is -8!


Another example:

3-5. So that's 3 (Keep it) + (Flip to add) -5 (Change sign). So that's 3+-5. Since signs are different, find the difference and sign is largest absolute value. Answer is -2!


One final example:

-3 - -5. -3 (Keep it) + (Flip to add) 5 (Change sign). That is now -3 + 5. Signs are different so find the difference and sign is largest absolute value. Answer is 2!

Real World Applications

Football. Gain of yard and loss of yards from the line of scrimmage. GR gained 5 yards. 0+5=5. They then lost 7 yards. From line of scrimmage, that's 5-7 or 5 + -7= -2 from line of scrimmage.


Temperature. Temperature was 15 degrees at noon and dropped 20 degrees by 6:00PM. 15-20 is 15 + -20. Temperature at 6:00PM was -5 degrees.