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In math, you often usmam.orge variables: letter of the alphabet (and sometimes also Greek letters) that stand for an unknown value, or a amount that have the right to vary.

With variables, you have the right to represent variable quantities, such as a price the varies, the variety of items you great to buy, or a gym membership wherein the all at once costs vary relying on the variety of months you space willing to be a member, and also so on.

So in math, expressions and also equations regularly usmam.orge variables. But variables room also basic components that functions, wherein one input, x, has actually only one output, generally y. Any letter or symbol deserve to represent a variable, or unknown, as they"re periodically called; it renders no difference whether you usmam.orge a, k or x.

But there space some conventions in math. Specific variables are usmam.orged in specific contexts, prefer y = mx + b or ax² + bx + c in Algebra. For example, in Geometry, Greek letter are often usmam.orged for angles, resources letters are usmam.orged for vertices and lowercase letters are provided for sides.

In mathematics rules, laws, theorems, and also standardized formulas, x generally represents the unknown worth you have to solve for, while variables favor a, b, c, or m are supplied as parameters or coefficients, whereby the rule always works the same, no issue which integer or actual number you substitute in. In functions, you"ll uncover that x and y room usmam.orged most of the time, wherein y stands for a worth that counts on the value of the variable x.

Interpret the structure of expressions. CCSS.MATH.CONTENT.HSA.SSE.A.1

Sarah is kicking Eric`s butt at a map game. The goal of the game is to do a right with five cards.

Sarah draws another card. She acquired lucky, it"s a wildcard. Let"s have a watch at she hand. Sarah has actually a good hand. She already has a two, three, four, and five. And also with the wildcard she"s the winner! The wildcard have the right to represent the one map or that can also represent the six card. A wildcard can take top top the value of any type of card in the deck.

### Variables in Algebra

In Algebra, there is a principle that is similar to the wildcard. Variables space letters or variousmam.org other symbols usmam.orged to stand for unknown number in algebraic equations and also expressions. We have the right to say: A change is a letter or symbol the represents a amount that have the right to vary. For example x, y or a or whatever you choose. A variable have the right to represent an unknown number in an equation. In this example subtraction equation, the variable, x, is equal to two.

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### usmam.orging Variables in Algebraic Expressions

Let"s see jusmam.orgt how variables can be supplied in algebraic expressions.Imagine you have a smartphone contract. The monthly charge for your cell phone is the fixed, monthly price plusmam.org fifteen dollars per gigabyte the data. The variable x is same to the variety of gigabytes. You have the right to write this as an algebraic expression: 25\$ + 15\$ · x. V this expression, you can calculate your monthly charge depending upon what data setup you need.