like i said, the only thing that seems to make sense to me is to have two separate equations. where did this equation come from anyway? was it one that you made up, or was it given to you. tell me the question that you started with
i think you made a typo. what hinted that to me is the last equation you typed. you had =64z^2 = -121. it makes no sense to have the = in front of the 64 like that. are you sure it shouldn't be a minus sign, as in a - ?
look at the book again, maybe you should have: 4x - 5 = 3(2x + 7) and -64z^2 = -121