I'm trying to do problems on Khan Academy in the area of 'rewriting exponential expressions.' I got one wrong and the answer is shown as:
= $3^x - 3^x/9$
= $3^x (1 - 1/9)$
= $8/9 * 3^x$
I don't understand step 2... where did the $1 - 1/9$ come from?
Thank you