1. Day 4 – Subtracting Integers

2. How to subtract integers with algebra tiles 1. Change the problem to addition  Keep the first number the same  Change the problem from subtraction to addition  Make the last number its opposite 2. Now follow adding integer rules  Same sign – add the numbers keep the sign  Different signs – subtract the numbers, keep the sign of the greater absolute value

3. Here’s how you change the problem! -8 – 7 -8 + -7 -8 stays the same Subtraction becomes addition 7 changes to its opposite -7 *Then follow addition rules or use algebra tiles to solve Answer: -15

4. You try & change these problems 1. -4 – 8 = 2. 9 – 17 = 3. 3 - -5 = 4. 6 – 10 = 5. -8 - - 17 = 1. -4 + -8 = 2. 9 + -17 = 3. 3 + 5 = 4. 6 + -10 = 5. -8 + 17 = Changed Problems Now follow adding rules or use algebra tiles to solve! 1. -12 2. -8 3. 8 4. -4 5. 9

5. Solve these practice problems! 1. -5 - -4 = 2. 4 - -7 = 3. -12 – 4 = 4. 9 - -5 = 5. -5 - -9 = 6. -10 – 8 = 7. -4 - -4 = 8. -12 -3 = 1. -1 2. 11 3. -16 4. 14 5. 4 6. -18 7. 0 8. -15

6. Word Problems 1. A submarine is situated at 450 feet below sea level and sinks 75 feet. What is the new position of the submarine?  -450 – 75 = -525 feet 2. The temperature at 8pm was 6°F. At 2am the temperature decreased 13 degrees. What was the temperature at 2am?  6 – 13 = -7°F