Lesson 1 of 19
Two moves the same way
Show on a big screenA quiz team starts at 0. It loses 3 points. Then it loses 4 more. What is the score now?
Step 1 of 4
- Start at 0.
- Add −3. Walk 3 left.
- Add −4. Walk 4 more left.
- Sum = −7.
The score is −7.
Each loss is a move on the line. A move's size is its number of steps. Its side is left or right.
Rule: two moves the same way? Add the sizes. Keep the side. Sum — the answer to an add.
(−3) + (−4) = −7. Both moves go left, so they join into one longer walk. It is 3 + 4 = 7 steps left.
Set two moves in the lab. The marker walks from 0.
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Try the lab to finish this lesson.