To add and subtract numbers always begin counting from zero. When adding positive numbers, count to the right. When subtracting positive numbers, count to the left. Calculate 4 - 5 - 3. Imagine moving ...

To add -4 and 5, draw the starting number on a number line and count to the right when adding positive numbers. What is the difference in temperature between a desert at 40 °C and a mountain top at -2 ...

“Man, I didn’t do nothing,” students often said to me when I spoke with them about their behavior. “My point exactly,” I replied. “If you didn’t do nothing, you must have done something.” It was after ...