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One definition of the English verb to distribute is to spread out.
The distributive law is one of the most frequently used tools in algebra,
and tells how multiplication gets ‘spread out’ when it interacts
with addition—it gives a different order of operations that can be used.

The basic statement of the distributive law is deceptively simple.
Many important tools, however, are consequences of this law.
One of the most famous is ‘FOIL’, which we'll see in the next section
is a memory device for correctly multiplying expressions of the form [beautiful math coming... please be patient] $\,(a + b)(c + d)\,$.

The distributive law offers two different orders of operation that always give the same result:

• The expression [beautiful math coming... please be patient] $\,a(b + c)\,$ specifies this order:
  add $\,b\,$ to $\,c\,$;   then multiply $\,a\,$ by this sum.
• The expression [beautiful math coming... please be patient] $\,ab + ac\,$ specifies this order:
  multiply $\,a\,$ and $\,b\,$;   multiply $\,a\,$ and $\,c\,$;   then add these results.

One effective visual way to understand the statement of the distributive law is to use areas (see below).

Form a rectangle with height [beautiful math coming... please be patient] $\,a\,$ and width $\,b + c\,$.
The area of this rectangle is height times width:   [beautiful math coming... please be patient] $a(b + c)\,$.
However, the area can also be found by summing the areas of the two smaller rectangles:   [beautiful math coming... please be patient] $\,ab + ac\,$.
Thus, [beautiful math coming... please be patient] $\,a(b + c) = ab + ac\,$.

It helps some students first learning to use the distributive law to draw the following arrows: