Why not? Because every math system you've ever worked with has obeyed these properties! You have never dealt with a system where a×b did not in fact equal b×a, for instance, or where (a×b)×c did not equal a×(b×c). Which is why the properties probably seem somewhat pointless to you. Don't worry about their "relevance" for now; just make sure you can keep the properties straight so you can pass the next test. The lesson below explains how I kept track of the properties.
725 inches long.
<span>the height of the parallelogram?
</span>
The answer is : 46.4758001545 ( in square root )
You could use the proportion 3:1.
Per 3 feet, there is 1 yard.
For every 3 feet, there is an additional yard.
The ratio is 3 to 1, or 3:1
Your fully factored expression should be 2*(8a+5).
