Question

Select the factors of 10ax + 5bx − 8ay − 4by.

(2a + 4y)(5x − b)

(2a − 4y)(5x + b)

(2a − b)(5x + 4y)

(2a + b)(5x − 4y)

Answer 1

Let's start by factoring 5x out of these two terms,
\[\Large \color{royalblue}{10ax+5bx}−8ay−4by\]Which gives us,\[\Large \color{#FE2E64}{5x(2a+b)}−8ay−4by\]

Next let's factor -4y out of these two terms,\[\Large 5x(2a+b)\color{royalblue}{−8ay−4by}\]Giving us,\[\Large 5x(2a+b)\color{#FE2E64}{-4y(2a+b)}\]

From here you'll want to recognize that each of our terms has a common factor, I'll color them so it's easier to see.\[\Large 5x\color{royalblue}{(2a+b)}-4y\color{royalblue}{(2a+b)}\]Our next step is to factor (2a+b) out of each term, do you understand how to finish it up? :)