What is the standard form of #y= (x+3)(1-3x)-7x#?
To demonstrate what is happening:
Consider the product
We all know that the answer is 6.
We also know that
But what if we wrote 3 as
This is still so
The distributive property of multiplication simply means that we can write this as:
Can you see the way that multiplication by the 2 is 'spread around' (that is not a math term!!)
Doing the same thing with your question:
Consider just the brackets part:
Putting it all together:
Collecting like terms gives:
It just takes a little practice that is all!