Only like terms can be subtracted or added in algebraic expressions.
the reason you use letters in algebraic expressions is because you don't know the number so a letter replaces it.
I think it is important because you need to know it when you get older.
Variable is any letter used in an algebraic expression, and can vary (change form) to be any number, and one variable means the same number in any single algebraic expression. Usually algebra is simplifying the expression or equation until you know what the variable is equal to.
Learning the expressions is the same thing as learning your multiplication tables - it helps you to understand algebra. And algebra allows you to understand things like logic, statistics, and all sorts of calculations where you don't know enough numbers to do a straight addition or multiplication or subtraction or division.
Normally you don't take algebra in 7th grade, but if you place into it you will learn things like slope, simplifying algebraic equations and so on. It is not the easiest thing to do as a seventh grades, as I would know, but it isn't REALLY hard. You just need to pay attention to your teacher.
the reason you use letters in algebraic expressions is because you don't know the number so a letter replaces it.
I think it is important because you need to know it when you get older.
Variable is any letter used in an algebraic expression, and can vary (change form) to be any number, and one variable means the same number in any single algebraic expression. Usually algebra is simplifying the expression or equation until you know what the variable is equal to.
Algebraic expressions are useful for translating problems into the language of mathematics. An algebraic expression for the problem "6 times the sum of 4 and y" would be: 6(4+y) = 24 + 6y.
Learning the expressions is the same thing as learning your multiplication tables - it helps you to understand algebra. And algebra allows you to understand things like logic, statistics, and all sorts of calculations where you don't know enough numbers to do a straight addition or multiplication or subtraction or division.
You need to find the common denominator in order to add or subtract them. You can only add or subtract "like things" and by finding a common denominator you make both rational expressions into things that can be added or subtracted.
An algebraic geometer is a mathematician who specializes in algebraic geometry.
Normally you don't take algebra in 7th grade, but if you place into it you will learn things like slope, simplifying algebraic equations and so on. It is not the easiest thing to do as a seventh grades, as I would know, but it isn't REALLY hard. You just need to pay attention to your teacher.
You will know if she has tensed and by her facial expressions
When you have an algebraic expression with variables in it, you need to know the the value of each variable. The value of the expression is found by replacing the variables with their values and simplifying. For example, evaluate 2xy-3x if x=5 and y=-1. 2xy-3x = 2*5*(-1) -3*5 = -10-15 = -25.
Replace each variables in the algebraic expression by its [known] value and calculate the value (ie evaluate) of the algebraic expression.
face expressions