They are both letters of the alphabet
yes
Real numbers have several properties, not just one. For example: one of its properties is that it they are dense - which means, more or less, that you can find a number that is arbitrarily close to any given number.
a variable (4 x y)
Whatever it want's to stand for
The function is f(x, y) = x/y where x, y are real, and y ≠0
The properties for real numbers are as follows:closure: for any numbers x and y, x + y is a real number.associativity: for any numbers x, y and z, x + (y + z) = (x + y) + z = x + y + zidentity: for any number x, there is a number, denoted by 0, such that x + 0 = x = 0 + xInvertibility: for any number x, there is a number denoted by -x such that x + (-x) = (-x) + x = 0Commutativity: for any numbers x and y, x + y = y + x.
It's any real number distinct from 0. For instance, in the expression x/y, where x and y are real numbers, y needs to be a nonzero real number. This is because otherwise the expression x/y is undefined (viz. x/0).
All real numbers, except 0, have a multiplicative inverse. For any real x, (x not = 0), there exists a real number y such that x*y = 1. This y is denoted by 1/x.
X and Y stand for the x and y of an ordered pair. You could plug in the coordinate for x.
The Y doesn't stand for anything. It is part of the word RAY. In fact, the X doesn't stand for anything either. They were called x-rays because the type of radiation was unknown at the time.
y = -|a(x + b)|
for any real numbers x, y and z: REFLEXIVE PROPERTY; x=x SYMMETRIC PROPERTY; if x=y, then y=x TRANSITIVE PROPERTY; if x=y and y=z then x=z