Algebra: Variables and Expressions

Front

What is a variable in algebra?

Back

A variable is a symbol, often a letter, that represents a number that can change or vary.

Front

What is an expression in algebra?

Back

An expression is a combination of numbers, variables, and operations (like addition and multiplication) that represents a value.

Front

Evaluate: 2(a - 5) + 2 when a = 15.

Back

22

Front

Evaluate: r(r – 9) when r = 11.

Back

22

Front

What is the value of x + y if x = 3 and y = 5?

Back

8

Front

Evaluate: -2x + -3y when x = 10 and y = -6.

Back

-2

Front

Evaluate: 4y – 5 when y = 6.

Back

19

Front

What does it mean to evaluate an expression?

Back

To evaluate an expression means to calculate its value by substituting the variables with given numbers.

Front

What is the order of operations in algebra?

Back

The order of operations is a set of rules that determines the sequence in which calculations are performed: Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right).

Front

What is the difference between an equation and an expression?

Back

An equation states that two expressions are equal, while an expression does not include an equality sign.