You're using the commutative property when you swap the order of factors in a multiplication:

and you use the associative property when you regroup the products of more than 2 factors in a different way:

So, you're constantly alternating between associative and commutative. Try to see which property you're using in the first step, and then keep alternating between the two!
Answer:

Step-by-step explanation:
The slope-intercept form of an equation of a line:

<em>m</em><em> - slope</em>
<em>b</em><em> - y-intercept</em>
The formula of a slope:

We have the points (3, 12) and (5, 9).
Substitute:

Put the value of a slope and coordinates of the point (3, 12) to the equation of a line:


<em>add
to both sides</em>

Finally:

Earths diameter is about 7,927 miles.
The relationship between cm and m is
1 cm = 0.01 m
Multiply this equation by 0.05 to get the value you want.
0.05 cm = 0.0005 m
Step-by-step explanation:
The answer with explanation is in the image.