How do you simplify #(a + b)(a - 2b)#?

1 Answer

When you say simplify I'm going to take it as expand since factoring an expression is sometimes a way of simplifying it.
The answer will be #a^2 -2b^2-ab#

Explanation:

You simply multiply out each factor.

So you start by multiplying the #a# in #(a+b)# to each term in #(a-2b)#.
You will get #a^2-2ab# as the first portion of the answer.

So now you will do the same with the #b# in #(a+b)#.
Then you get #-2b^2+ab#.

Now you add #a^2-2ab# and #-2b^2+ab# to get #a^2 -2b^2-ab# .