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Frustrating that op doesn't straight answer the question. I think what he's getting at is that you can do the usual steps without having to interpret what the mean. For example, you don't have to say that you're subtracting 8 from 20. Instead you say that all things without x must be on the same side, and signs change when you move across. So one step is x+20-8=3x. Nevermind what those symbols mean, you just memorize the rules. At the end you have x=(20-8)/(3-1) and you put that into the calculator.

To me this seems that you're hacking the system. You're avoiding learning how to think and understand, you're just learning how to pass the class.

That said, I cannot concieve that some kids don't understand 20-8. I wish I could chat to some of them to see what's going on.




> To me this seems that you're hacking the system. You're avoiding learning how to think and understand, you're just learning how to pass the class.

I can certainly grasp that these are literally different, but are they practically different for most people?

Eg I know that some of my clothes need to be washed with cold water. I don't know why, but it's never made a difference in my life.

I know my car needs oil changes, but I don't specifically know why. Some kind of lubrication, but for what and why it goes bad I have no idea.

We all do hundreds of things algorithmically without really understanding what we're doing or why. We know enough to get the answer we want and that's good enough.

The kids that do algebra algorithmically probably aren't going to be math professors, but neither am I, and there are plenty of lucrative and productive professions that are fine with getting the right answer without knowing why.

On some level, most people are doing arithmetic algorithmically anyways, based on rules structured around base 10. Ask some people you think have passable arithmetic skills to do addition and subtraction in like base 5 and watch the smoke come out of their ears. I'm not casting aspersions, I'd have a hard time too past a couple digits.

I would wager most of them can't explain why we carry numbers over, they just know it needs to happen to get the right answer. I don't think I'm much better; I'm sure there are dozens of things in basic math that I just do without really understanding why.

> That said, I cannot concieve that some kids don't understand 20-8.

I would almost put money down that it's around carrying the 1's. I've met a few people that struggled with arithmetic, and they almost always get lost around carrying over numbers.


Regarding doing things algorithmically without understanding what's going on: sure, you have a point no doubt. But here's my counterpoint. What is the point of school? If you're teaching kids because you want them to be able to solve problems, why teach them algebra? How many times in their life does an average person have to find the solution to x+20=3x+8 to solve a real life problem? If you want to teach useful algorithms you should get rid of algebra and have schools teach taxes, personal hygiene, physical exercise, maintenance of house, car, etc and stuff like that.

But if the point of school isn't "teach them practical algorithms", but instead learning how to think, then it makes perfect sense to teach them equations, and have them actual understand.

I'm short, if the point of school is to learn how to think, teaching them some mysterious algorithms isn't going to achieve that. If the point is to learn useful algorithms, I can think of 100 better things than algebra.

So which one is it?


With this explanation, you've inadvertently convinced me of the op. Being able to get to the "x = number" is the whole point of algebra. More often, students find the difficulty in trying to do arithmetic on things that can't be(what's x +y? it isn't xy and it isn't some new letter).

Doing this way means that you've actually understood algebra, and honestly, the only step of memorization is the substraction itself.

Whether you pull out the calculator at 2 +3, or (23449)/(!6 + root(34/5) ) is sorta irrelevant.


> Doing this way means that you've actually understood algebra, and honestly, the only step of memorization is the substraction itself.

No, not really. If you understood what an equality and a variable means, then you could solve it without having to go thru algorithmic steps.

> More often, students find the difficulty in trying to do arithmetic on things that can't be(what's x +y? it isn't xy and it isn't some new letter).

I'm beginning to suspect that you yourself struggle with arithmetics.




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