Algebra, Chapter 2, Lesson 7, page 89.
Using the Distributive Property
The distributive property of multiplication over addition and subtraction is:
`a(b+c)=ab+ac` and `a(b−c)=ab−ac`
You can also combine LIKE TERMS ONLY IF THE VARIABLE AND THE EXPONENT OF THE VARIABLE ARE EXACTLY THE SAME!
Examples, (remember to use the wacky arrows!):
`9(x – 5) = 9x – 9(5) = 9x – 45`
`-4(x – 2y + 3z) = -4 * x – (-4)(2y) + (-4)(3z)`
`= -4x – (-8y) + (-12z) = -4x + 8y – 12z`
(don’t forget the change-change or bling-bling, double negative thingy …)
Here is a link from purplemath.com about the distributive property with more examples.