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You are not logged in. #1 20050827 08:01:19
AlgebraHi, this is my first post here. Let me give everyone a little background. My son is in 7th grade and is just beginning algebra. It's been a while since I've been in school and I'm trying to help my son. While checking his homework I cam across a problem that I thought he'd done wrong. We worked it together and came up with the answer. He went to school the next day and the teacher told him the answer he had was wrong. I disagreed and sent a note to the teacher asking her where we'd gone wrong. She sent home an answer that I'm still not satisfied with. My son (being the smart kid he is) went into Excel, typed in the expression (he simply entered the numbers instead of the letters) and Excel evaluated it with the answer that we got. #2 20050827 08:46:09
Re: AlgebraI think the teachers answer is right, in the order of operations it goes: parentheses, exponets, multiplication, division, addition, then subtraction. So in the problem first you would put in the given variables, (2(2) + 2(4) / 2(6), then (4 + 8) / 12, then 12 / 12, which simplifys to 1. #3 20050827 08:54:55
Re: AlgebraWelcome to the forum, frostysmom ! "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #4 20050827 09:17:42
Re: AlgebraThanks alot  I looked at the PEMDAS web page and I understand it to be like I said. In other words, multiplication and division, working from left to right whichever comes first. And in my mind, it supports my answer. #5 20050827 09:44:58
Re: AlgebraI think I see the problem, it is what order to do "/2x". Do you divide by 2 then multiply by x? In other words: "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #7 20050827 10:16:14
Re: AlgebraNo, it would be 1 because we would mulitiply "2x" first. "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #8 20050827 10:25:41
Re: AlgebraI'm sorry but I don't understand why you would multiply 2x first? That's what's really getting me...There aren't parentheses around the 2x so why wouldn't you divide then multiply? #9 20050827 11:37:14
Re: Algebrawhen it comes to division or multiplication, it doesn't matter which one u do first. u can either divide right away: 