OPPOSITES – 7.NS.1b
Goal: Students will be able to design a model to illustrate that the sum of any number and its
opposite is zero.
Develop task: Opposites – Part 1
This is a bell-ringer type task to be done individually; some students may
not answer the questions as expected, but the idea is to get them thinking
about what an opposite is in a non-mathematical way.
Anticipate: Some students may not know the opposite of purple; otherwise, it’s pretty
straightforward, and easy for most students to do.
Solidify task: Opposites – Part 2
The activity with the chips would be done in pairs. The magic square would
be done individually to begin, then in pairs after ~5 minutes.
Anticipate: Students may not be familiar with the +/- chips. Some students may try to
model by putting the chips in the shape of the number. Some may try to
model -2 to using - + +. Students may not be familiar with magic squares.
You may need to walk through the example magic square.
Practice task: Opposites – Part 3
Anticipate: Have students do # 1 & 2, and have a discussion about “additive inverse.”
Name______Date______Period______
Opposites - Part 1
Name the opposite of the following:
1. White: ______7. Wet: ______
2. Purple: ______8. Long: ______
3. Hard: ______9. Same: ______
4. Smooth: ______10. West: ______
5. Far: ______11. Hot: ______
6. Heavy: ______12. Left: ______
13. Name an instance when wet is better than dry: ______
14. When is dry better than wet? ______
15. Name something that you prefer to be long, not short: ______
16. Name something that you prefer to be short, not long: ______
17. What is better when there’s more? ______
18. What is better when there’s less? ______
Consider all the pairs of opposites listed above:
19. Is there one word of each pair that is always better than the other? ______
20. Does OPPOSITE mean worse? ______Does it mean better? ______
Name______Date______Period______
Opposites - Part 2
Task 1: In your resource tray, you will find yellow and red chips.
Red = negative
Yellow = positive
Arrange the chips to model the numbers below. You must represent each number at least four different ways. Sketch your representations below.
a) 5 b) -2 c) 0
Task 2: Complete the following magic square. The sum of each row, column, and
diagonal should equal zero. Use integers. No number may be used more than
once.
Example:2 / 7 / 6
9 / 5 / 1
4 / 3 / 8
/
0
This one adds up to 15.
Name______Date______Period______
Opposites - Part 3
1. Choose any pair of opposites on the above number line. Which number is in the
exact middle? ______
2. Explain what makes two numbers opposites: ______
______
______
Write the following in simplest form using symbols and numbers:
3. the opposite of five: ______7. the opposite of sixteen: ______
4. the opposite of nine: ______8. the opposite of twenty: ______
5. the opposite of negative two: ______9. the opposite of negative one: ______
6. the opposite of negative eight: ______10. the opposite of negative forty: ______
Write the opposite of the following numbers:
11. 19: ______17. -32: ______23. -638 : ______
12. 598: ______18. -55: ______24. 945 : ______
13. -12: ______19. -99: ______25. -183: ______
14. -6.39: ______20. 18.635: ______26. 3: ______
15. 14.01: ______21. -12 : ______27. -745: ______
16. -10,023: ______22. 83 13: ______28. -412: ______
Beginning with the phrase, “the opposite of,” write the following numbers in words. The first one is done for you:
29. 16 is __the opposite of negative sixteen______
30. -5 is ______
31. 19 is ______
32. -2 is ______
33. 10 is ______
34. 1 is ______
35. -7 is ______
Solve the following:
36. 11 + (-11) = ______
38. (-6) + 6 + (-6) + 6 + 5 + (-5) = ______
37. (-15) + 0 + 15 = ______
39. A diver started at sea level (0 feet altitude) and climbed a cliff which is 250 feet above
sea level. He then dove into the sea to a depth of 50 feet. He swam back up to the
surface of the sea. What is his present altitude?