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Why aren't we using the multiplication sign?

Great question. In algebra, we do indeed avoid using the multiplication sign. We'll explain it for you here. Created by Sal Khan.

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• at , why do mathematicians use "X" as a variable more often that most?
• x is actually the latin replacement for the arabic word that means "unknown" or "something." Here's a short video about it on Tedtalks: http://www.youtube.com/watch?v=YX_OxBfsvbk

Hope you foound this interesting :)
• Why couldn't you just use a different symbol than x?
• You can use any letter or symbols to represent your number.
(1 vote)
• is this correct way to solve 7+4b b=3

7+4b
= 4*3
=12+7
=19

is there another way I can solve this problem
• yep,that's the way I do the equation. But I do that more explained.Otherwise I can't understand the question.
7+4b,b=3
=7+4*(3)
=7+12
=19
only a little bit explained.
• At Sal says we can use a dot for a multiplication sign instead of an x. Why do mathematicians use a dot, and not some other sign?
• If you're asking why we use the dot specifically, it probably just arose because of its simplicity. We multiply things a lot in math, and mathematicians like to be efficient when they write. The dot (it's actually called an "interpunct" to be more specific) is so simple and short to write, that's probably why we use it instead of another symbol.
• Hang on, if there is no space between the number (2), and the variable (x), why is it multiplication? It could be any operation! Please answer!
• It's just a math convention that makes later math easier. It might make more sense if you think of how you might talk about several of a certain number. You would say you had 3 dozen eggs, not 3 times a dozen eggs. Or you might say you have 8 pairs of socks, not 8 times 2 socks. In the same way we say 3x or 8y.
• Would my teacher take points off, if I don't use ˑ ?
• Hi,
Only in algebra and combining like terms, and some word problems that has the variable "x" is a very good time to use the . when not to get confused with the variable "x", even though there are no variables that are "x". Otherwise if he gets confused between "x" as a variable and "x" as multiplication sign, he would take points off. Hope that helps, and good luck! ;)
• why do we use Greek words in geometry?
• Ancient Greek mathematicians discovered many geometric concepts. One of them, Euclid wrote a book called The Elements that was used for many years as a textbook for geometry. So many of our conventions used today in Geometry likely date back to the methods that he used.
• Is it ok to use Google