00:48duration 48 seconds
Prealgebra 2.2.1
2 + (-5)
01:47duration 1 minute 47 seconds
Prealgebra 2.2.2
- 1 + -3
00:58duration 58 seconds
Prealgebra 2.2.3
- 5 + (-7)
01:09duration 1 minute 9 seconds
Prealgebra 2.2.4
-4 + 0
00:47duration 47 seconds
Prealgebra 2.2.5
3 + (-5)
01:13duration 1 minute 13 seconds
Prealgebra 2.2.6
1 + (-5)
01:43duration 1 minute 43 seconds
Prealgebra 2.2.7
-12 + (-7)
01:16duration 1 minute 16 seconds
Prealgebra 2.2.8
-8 + 8
01:45duration 1 minute 45 seconds
Prealgebra 2.2.9
12 + (-2) + 14 + (-5)+ (-12)
03:09duration 3 minutes 9 seconds
Prealgebra 2.3.1
a - b = a + (-b)
01:41duration 1 minute 41 seconds
Prealgebra 2.3.2
5 - 8
00:43duration 43 seconds
Prealgebra 2.3.3
3 - 7
00:50duration 50 seconds
Prealgebra 2.3.4
-14 - (-23)
00:29duration 29 seconds
Prealgebra 2.3.5
-12- 30
00:45duration 45 seconds
Prealgebra 2.3.6
-20 - (-17)
00:21duration 21 seconds
Prealgebra 2.3.7
4 - (-9)