Adding integers with tiles and number lines Lesson 2.2 and 2.3
To add two positive integers: (+3) + (+2)...you can use tiles. Combine the tiles. There are 5 yellow tiles. They model +5 +2 So, (+3) + (+2) = +5
To add two negative integers, you can also use tiles. (-3) + (-4) = Combine the red tiles. There are 7 tiles. They model -7. -3 -4 So, (-3) + (-4) = -7
To add a negative integer and a positive integer, you can use tiles -3 First, find the zero pairs... +5 There are 3 zero pairs. Count the tiles that are left...there are 3 yellow tiles left. They model +3. So, (-3) + (+5)= +3
The temperature rise +5˚C, then, it falls 8˚C. A) represent the above statement with integers. B) Find the overall change in temperature.
A) +5 indicates a rise in temperature. -8 indicates a drop in temperature. The equation is: (+5) + (-8) = b) Using tiles to model temperature change: +5 -8 There are 3 red tiles left. That means the answer is -3. So, the overall change in temperature is -3˚C