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You are not logged in. #1 20130811 04:51:50
dilation problemWhen a square of area 4 is dilated by a scale factor of k, we obtain a square of area 9. Find the sum of all possible values of k. Genius is one percent inspiration and ninetynine percent perspiration #2 20130811 05:15:44
Re: dilation problemWhen all lengths are increased by a scale factor k, each side of the square is k times bigger so the area gets bigger by a factor of k squared. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #3 20130811 05:29:05
Re: dilation problemi got one value for k (3/2) but i don't know how to get the other one Genius is one percent inspiration and ninetynine percent perspiration #5 20130811 05:48:36
Re: dilation problemwhat do you mean by just say minus the same for the second one Genius is one percent inspiration and ninetynine percent perspiration #6 20130811 05:50:05
Re: dilation problemi got 0 since 3/2+3/2 is 0 Genius is one percent inspiration and ninetynine percent perspiration #7 20130811 06:01:20
Re: dilation problemI suppose that is correct. Bit strange though. If you got the first k wrong, but knew to make it minus, you'd still get 0. Wrong working but right answer. Hhhmmm. Worrying. If I was testing a student, I'd ask for both answers, just to be certain. Is this work computer marked by any chance? You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #8 20130811 06:05:03
Re: dilation problemwhat do you mean by computer marked? Genius is one percent inspiration and ninetynine percent perspiration #9 20130811 06:15:57
Re: dilation problemIf a student hands in work on a sheet of paper I can view all the working and award marks for good maths. Some online courses only want answers that can be checked by a computer. So it is necessary to submit single letters (if multichoice) or numbers so that the program can do an exact comparison. It's easy for the course administrators but somewhat poor at detecting student misunderstandings. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #10 20130811 06:22:37
Re: dilation problemyeah its for my hw on aops Genius is one percent inspiration and ninetynine percent perspiration #11 20130811 06:26:09
Re: dilation problemso i guess it is computer marked Genius is one percent inspiration and ninetynine percent perspiration 