Negative 1, it's going to be 0 plus negative 1. The value of thisĮxpression will change depending on what the An expression wouldīe something like what we saw over here, x plus 5. Really just a statement of value, a statement of Important to realize the distinction between anĮxpression and an equation. And this is in theĬontext of an expression. Variable, and its value can change depending on the context. Know, negative 7, then x plus 5 is going to be equal to. If x is equal toġ, then x plus 5, our expression right over here, Some value depending on what the value of x is.

Them, but they're really just values in expressions This a little bit already- we start dealing with The algebraic world- and you probably have seen Know exactly what numbers we're dealing with. We know what these numbersĪre right over here, and we can calculate them. With basic arithmetic, we see the concrete The equality part of the inequality would form a line or curve which could be solid or dashed and shading either above or below this line or curve.

On a number line, it creates ray(s) or a line, and it is an area on the Cartesian Plane.

The inequalities (greater than, greater than or equal to, less than, less than or equal to, and not equal to) allows for multiple solutions. With a single variable, the solution is a point on the number line, and with two variables it ends up as a line or curve on a Cartesian Plane. With two variables, an equation can be a function if each input (x in the equation above) has at most one output value (y in the equation above). Examples could be 2x + 5 = 3x - 9 or y = 3x - 2.

This will allow us to solve or isolate a variable. Next, we can set two expressions equal to each other by creating an equation. All we can do with these is simplify or evaluate for given values. Expressions have one or more terms which are separated by plus and minus signs.

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