Question

use the chips to add.
-2 + 5
(a) show how to do the problem. click here to learn more about these chips.
(b) -2 + 5 = \square

Explanation:

Step1: Represent -2 with chips

Take 2 red (-) chips: $(-1) + (-1) = -2$

Step2: Represent +5 with chips

Take 5 yellow (+) chips: $(+1)+(+1)+(+1)+(+1)+(+1) = +5$

Step3: Cancel zero pairs

Pair each (-) chip with a (+) chip. 2 pairs cancel out: $(-1+1)+(-1+1) = 0$

Step4: Count remaining chips

3 (+) chips are left: $(+1)+(+1)+(+1) = 3$

Answer:

(a)

1. Place 2 red (-) chips in the workspace to represent -2.
2. Place 5 yellow (+) chips in the workspace to represent +5.
3. Match each red (-) chip with a yellow (+) chip; these 2 pairs cancel each other out (sum to 0).
4. 3 yellow (+) chips remain in the workspace.

(b) $-2 + 5 = 3$