I'm stuck in the highlighted part of the problem....
I did not see that! Thank you.
asilvester635, your first line was . Your next line should be (you have subtracted from both sides). But then you have " ". My guess is that you intended to multiply by -1 but, again, you must have "= 0" and you did not multiply the "24z" by -1. You should have . Obviously both "4" and "z" divide each term so you can factor 4z out: . (3)(2)= 6 and their difference is 1 so we can further factor as .
Now what? Remember the basic reason for factoring: "if ab= 0 then either a= 0 or b= 0".