2x + 3 = 9
x = /2 [or 12?]
Mathematics - simple algebra.
The handwriting is large and generally clear, even though this class appears to only have one student in it, and he sits at the very front. It might be worth advising the student to have his eyes tested if he is unable to read smaller text at this distance. Remember that poor learning may be as a result of poor vision - the student might not even be aware that he has a problem. If the teacher does keep her handwriting that size she will have to get a bigger whiteboard when she starts doing quadratic equations. Finally, when writing algebraic equations, it is preferable to do a more cursive x for the unknown symbol, to avoid confusion with a multiplication sign.
Unfortunately, the answer is unclearly written - is it 2? 12? 1/2? Whichever of these it is meant to be, it is wrong. Here is the correct calculation:
2x + 3 = 9
Subtract 3 from both sides:
2x = 6
Divide both sides by 2:
x = 3
Given the differences in handwriting in the '2's though, it is possible that the teacher left the answer blank for the student to fill in, and is pointing for him to return to his desk. Either way, it is better to show one's working, so that if an error is made, but followed by correct calculations, the examiner may still give marks for the later parts of the answer, even if incorrect.
5/10 - could do better.
I see the original equation as "2x ÷ 3 = 9"
ReplyDelete(2 x divided by 3 gives 9)
Thus multiplying each side by 3 gives
2x = 27
x = 13.5
Which means she still had it wrong.
I'm pretty sure it's _/2, she just didn't fill the blank (6).
ReplyDeleteBut what intrigues me is the picture above the blackboard, who is this?...
yeah, it is just not finished.
ReplyDeletethe "/2" is just a discription what has to be done in this line. we had to do it the same way. it's not wrong, just not complete.
funny though, that you are all here because of nerdcore ^^
ReplyDeleteHe doesn't have a pen / marker, so that would seem to rule out the answer being his. I'm not sure the teacher understands the subject well enough to be teaching it. Perhaps she's a disciplinarian. Keep that in mind, kids -- if you can't do basic algebra, the only job left to you might be Detention Monitor.
ReplyDeleteReynardo: great question. I can tell you it's not Galois, Newton, Leibniz, Euler, Descartes, or Riemann. The high collar and lack of wig was what made me think Galois originally. I also tried a few non-mathematicians -- Thoreau, Emerson, Coleridge. Coleridge is too fat but otherwise the closest to the mark.
ReplyDeleteI'm pretty sure that the "/2" thingy is a mark for student's work. You see, in Russia (and this is definitely filmed in Russia because of Russian posters near the whiteboard), teachers often draw such a diagonal line and then write the mark beside it.
ReplyDelete/2 could be an incomplete work.
ReplyDelete2x + 3 = 9
x = ?/2
Which is correct since
2x= 9-3
x = 6/2 = 3
Speaking as a maths teacher, the /2 thing is definitely an incomplete line. She is referring to the next two steps,
ReplyDelete2x = 6,
then
x = 6/2 = 3. The blank space before /2 is for a 6.
popoffka - I do that / thing but in this case it isn't, since it has to be much further to the right, or it leaves no space for the answer. A maths teacher would never write the mark that close to the answer, it's confusing.
ReplyDelete2 is a mark, exactly.
ReplyDeleteanother russian
I'm from Russia. This is Russian film.
ReplyDelete„2” is the worse mark in Russian school.
It seems to me this student is going to take punishment for bad math skills.
Тупые америкосы, вы кого математике учить собрались, если даже не можете понять - что и почему написано на доске в этой фотке?
ReplyDeleteThe founding father above the board would be so proud.
ReplyDeleteI'm another Russian, your blog is now becoming well-known here. And that's a mark for sure, and an answer is not given by a student, he failed to complete an equation. It's normal to write it so close. And about the portret - not founding father, maybe it's a portret of Russian mathematician - Ostrogradsky.
ReplyDeletePortrait looks like Hannibal Lecter to me. Is he well known in Russia?
ReplyDeleteThanks for everyone's input on this one - I am learning a lot about how maths is taught around the world.
ReplyDeleteThe picture above the blackboard shows the inventor of the binomial theorem, Francesco Binomi. http://ragefac.es/61
ReplyDeleteHi, the thing is, that 2 is a mark. Like F in the USA.
ReplyDeleteNice blog by the way :)
Apologies for being a white/black board racist here, but this is a whiteboard not a blackboard and should therefore be posted on the equally auspicious and excellent blog "whiteboards in porn" [which you shall duly create after reading this comment of course. Get to work!].
ReplyDeletep.s. thumbs up on an excellent blog.
p.p.s you may get more thumbs up on your new blog after you've set it up. You're stoked in anticipation right? Course...