00:01
Okay, let's take a look at this problem.
00:06
So if i look at the very first step, this is just using rules of place value.
00:15
32 is the same as three tens plus two.
00:19
The three is in the ten spot, the two is in the one spot.
00:23
23 is the same as two tens plus three.
00:30
Okay, so the next step's a one unit.
00:40
And you look at the two times ten as one unit.
00:43
All they've done in the next spot is rearrange the addition.
00:47
So they did the three times ten first, and then the two times ten second, and then the two, and the three.
00:57
And the also thing they did is they grouped them differently.
01:01
So i would say the second step is d.
01:04
It's the associative n, the commutative property.
01:08
Associative property because they change the way they're grouped, and commutative property because they change the order.
01:17
Now the next step i think is also a little bit difficult to see, but let's look at this right here...