Why does x stand for unknown?

Answer 1

X stands for unkown because someone chose it to be a main variable.

Answer 2

Many algebraic equations use letters to represent constants and unknown quantities. Convention has adopted a system where the first half of the alphabet is commonly used for constants and the second half is used for unknown values. Exceptions occur when the particular letter can represent a value of a quantity whose name starts with that letter. K or k is often used as a constant of proportionality. The letter c was selected to represent the constant speed of light. The letters x, y and z are often used to represent three unknowns such as specific values to be found on an X, Y, Z 3-D plot. Of course different fields of science may use letters (constants and unknowns) in equations that differ from use in other fields and it is helpful (required?) to define all letters unless their use is perfectly clear. E = mc2 (Einstein's equation) likely would be understood unless all the letters are re-defined in a particular paper (probably not a good idea).

Answer 3

x is used for simple one-dimensional algebraic expressions.

then later we add y and z to get two and three dimensions. we can then plot the results on an xy plane or use some computer graphics to visualize the results in a 3-D xyz view.

there are other conventions too.
in FORTRAN variables beginning with I, J, K, L ,M or N were INtegers (see IN -tegers). all the rest were real.

later i was introduced as the sqrt(-1) but when we go to plot imaginary numbers on a plane, we use x for the real and y for the imaginary part. this collided with the use of unit vecors i, j, and k where i is (1,0,0) j is (0,1,0) and k is (0,0,1) so engineers adopted j as the root of -1.

you will also find that a number of greek letters are used to express other special numbers and some arabic letters too.

so starting with x as the unknown is the beginning of a long tradition in mathematics.

Answer 4

Several hundred years ago mathematicians found it useful to distinguish between quantities that were known ahead of time and those that weren't known yet. A convention arose that the letters near the beginning of the alphabet A,B,C ... were used for knowns, and letters near the end of the alphabet, x, y, z ... were the unknowns.
Hope this helps.

Answer 5

That is just the way that it is!! Been that way for long time, like thousands of years. Maybe you can change it after all, they all of a sudden decided that Pluto wasn't a planet. Why did they do that? What did Pluto ever do to anybody? Pluto was just sitting out there minding it's own business and they had to go and fugg with it.

Nutcase, you are a nut!!

Answer 6

x stands as unknown its not a hard and fast rule you can choose "y" ,"z" or "p" as unknown.

Answer 7

X as a Roman numeral means 5
x between to numbers meas to multiply them

Answer 8

it just does, it must be traditional i suppose to refer to unknown as x, it's like saying why is a duck called a duck lol!

Answer 9

So that we may understand equations and utilize formulas...the x is the variable unknown

never thought of that til now...

Answer 10

because we don't know the number for x and we need to solve for it.