spirited away Posted May 1, 2006 Posted May 1, 2006 Ok, so i've got my math sats tomorrow, i feel pretty confident ( got an 8 in practice), but theres just one thing i cant get my head around and these revision books aren't really making it any simpler. Solving equations is a pretty dark area for me and i've jsut wasted 2 a4 pages trying to work out a probably simple sum that i jsut dont get. If anyone can help me, thanks . Its : 6 over x + 3 = 9 over 5 + 2x
mario114 Posted May 1, 2006 Posted May 1, 2006 I think it's x = .5 no, it isn't?? I'm confussed I, know were I went wrong, will be anotuher min...
spirited away Posted May 1, 2006 Author Posted May 1, 2006 My revision book says the answer is x=-1, dont know how to get there.
Nintendork Posted May 1, 2006 Posted May 1, 2006 SATS don't matter. I was in bottom set for English after I got shit SATS and I got an A in my GCSE. It's all application, who the hell thought 14 year olds would enjoy studying Beowulf? Retards. At GCSE you get to study some great stuff, shuv the SATS. Your starting point would be to get each side on an equal plane. ignore the division part and concentrate on the numbers you have to start with.
spirited away Posted May 1, 2006 Author Posted May 1, 2006 It's all application, who the hell thought 14 year olds would enjoy studying Beowulf? Retards. At GCSE you get to study some great stuff, shuv the SATS. with. Beowulf was complete rubbish IMO. These revision books are clogged up with stupid jokes, as if were in junior school... Over as in division.
mario114 Posted May 1, 2006 Posted May 1, 2006 I feel really bad, I'm doing A-level physics and this stupid equation keeps anoying me... I'll get it soon...
spirited away Posted May 1, 2006 Author Posted May 1, 2006 I feel really bad, I'm doing A-level physics and this stupid equation keeps anoying me... I'll get it soon... Maths is a bitch sometimes.
Guest Stefkov Posted May 1, 2006 Posted May 1, 2006 i am so not god at amths but ill ive it a try 6/x + 3 = 9/5 + 2x times both sides by x+3 = (x+3) x (5+2x) 5x + 2x squared +15 + 6x 6=9/11x + 2x squared + 15 now im confused. to think im actually in set 2 and going in for higer. HA. also i fucking hate To Kill a Mockingbird. it gets so tiriing after youve discussed Atticus for the 13th time. and Jem for the 8th time and also Scout for the 25th time.
Tellyn Posted May 1, 2006 Posted May 1, 2006 Sorry I couldn't help you last night SA, I'm not good at solving equations. At least we both still have a couple more days of revision, Science Paper 1 and 2 tomorrow. I'm at a high level 7 in science, so I'm not too worried. English, not so much either, just maths.
spirited away Posted May 1, 2006 Author Posted May 1, 2006 no problem telly, Stefkov, that was one of my theories for the answer but got stuck on same bit.
mario114 Posted May 1, 2006 Posted May 1, 2006 I've got to x-9 = 2x-10, and though I had it, but no...
Guest Stefkov Posted May 1, 2006 Posted May 1, 2006 i think it might actually be 6 = 9x + 27 .....------- .....11x + 2x squared + 15 6 x (11x + 2x squared + 15) = 9x + 27 66x + 12x squared + 90 = 9x + 27 66x + 12x squared + 63 = 9x 12x squared + 63 = -57x 12x + 63 = -7.55x 63 = -19.55x -1.84 = x what did i just do? wit you said the nswer in the book was -1, i nearly got it
spirited away Posted May 1, 2006 Author Posted May 1, 2006 i think it might actually be 6 = 9x + 27 .....------- .....11x + 2x squared + 15 6 x (11x + 2x squared + 15) = 9x + 27 66x + 12x squared + 90 = 9x + 27 66x + 12x squared + 63 = 9x 12x squared + 63 = -57x 12x + 63 = -7.55x 63 = -19.55x -1.84 = x what did i just do? wit you said the nswer in the book was -1, i nearly got it no idea...I'm gonna have another stab at it. This is some stupid sats question.
Guest Stefkov Posted May 1, 2006 Posted May 1, 2006 yeah id actually like to know at the answer is now.. maybe a maths teacher is registered here..... on these forums or someone good at maths?
spirited away Posted May 1, 2006 Author Posted May 1, 2006 The answer is -1, -1+3=2 6/2=3 5+2x=5+-2=3 9/3=3 But have no idea how you get to the answer.
system_error Posted May 1, 2006 Posted May 1, 2006 I am not sure what this "over" exactly means but I will give it a try (my maths english is not the best): 6/x + 3 = 9/5 + 2x 1. step get rid of the division stuff by multiplying with 5x 2. put everything on one side so you get something + something = 0 3 use the damn formula Solving quadratic equotations: if the equotation is like: ax^2 + bx + c = 0 then we can use this formula: x(1,2) = (-b +/- sqrt(b^2 - 4ac)) / 2a x1 = (sqrt(309) + 3) / 10 and x2 = (sqrt(309) - 3) / 10 sqrt = square root
Charlie Posted May 1, 2006 Posted May 1, 2006 http://www.hostsrv.com/webmab/app1/MSP/quickmath/02/pageGenerate?site=quickmath&s1=equations&s2=solve&s3=basic That website there gave the answer -1. I think you have to take the brackets to the top, which makes them power to the -1.
spirited away Posted May 1, 2006 Author Posted May 1, 2006 I am not sure what this "over" exactly means but I will give it a try (my maths english is not the best): 6/x + 3 = 9/5 + 2x 1. step get rid of the division stuff by multiplying with 5x 2. put everything on one side so you get something + something = 0 3 use the damn formula Solving quadratic equotations: if the equotation is like: ax^2 + bx + c = 0 then we can use this formula: x(1,2) = (-b +/- sqrt(b^2 - 4ac)) / 2a x1 = (sqrt(309) + 3) / 10 and x2 = (sqrt(309) - 3) / 10 sqrt = square root Woah taht stuff is way past what we have learnt:heh: By over i mean 6 --- x+3
Charlie Posted May 1, 2006 Posted May 1, 2006 Woah taht stuff is way past what we have learnt:heh: By over i mean 6 --- x+3 6/(x+3) is the correct way to write it / = divide (which is the same as 'over')
spirited away Posted May 1, 2006 Author Posted May 1, 2006 oh, kk. Still dont get it. Much of these questions coem up in the exam? Sorry if i wrote it up wrong...
system_error Posted May 1, 2006 Posted May 1, 2006 LOL that makes everything DIFFERENT, now please forget the stuff I posted earlier! So your equotation is: 6/(x+3) = 9/(5+2x) ......... / * (x+3)*(5+2x) 30 + 12 x = 9x + 27 ......... / -9x, -30 3x = -3 ........... / : 3 x = -1 Et Voila! Wasn't difficult at all. If you need a further explaination ask me.
Flaight Posted May 1, 2006 Posted May 1, 2006 lol. I misread the first post at first. I read it as 6/x + 3. That gives unclean answer. But you mean 6/(x+3), in which case, x is -1. I'd first get rid of divisions in any questions of this sort. Take the denominator and cross it over to the other side, so it becomes: 6 ( 5+2x ) = 9 ( x+3 ) then expand brackets: 30 + 12x = 9x + 27 which is 3x = -3 So: x = -1 EDIT: I see system_error also fell into the same trap the first time as I did. lol.
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