https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:intro-variables/v/what-is-a-variable 2023-05-23T10:28:13.689545116Z What is a variable? Variables in math are symbols, often letters, that represent different values in various situations. They help us understand and solve problems with changing values. For example, when calculating total earnings at a job with an hourly wage plus tips, a variable can represent the fluctuating tips, making it easier to determine total income. Sal Khan video https://cdn.kastatic.org/googleusercontent/Z0Ew0H4CUDZ7Hc0NbhfLe904T2e_lMEyScP69jTH-2Kcauq4mxzwzwDS-yQlWeQlDKGfOS3-podwVZQRor01fOc What is a variable? Variables in math are symbols, often letters, that represent different values in various situations. They help us understand and solve problems with changing values. For example, when calculating total earnings at a job with an hourly wage plus tips, a variable can represent the fluctuating tips, making it easier to determine total income. https://cdn.kastatic.org/ka-youtube-converted/tHYis-DP0oU.mp4/tHYis-DP0oU.mp4 198 Algebraic expressions https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-evaluating-expressions/v/expression-terms-factors-and-coefficients 2023-05-23T10:28:13.689545116Z Terms, factors, & coefficients In math expressions, terms are the components added or subtracted, factors are the elements multiplied within each term, and coefficients are the numbers multiplying variables. Understanding these concepts is crucial for effective communication and problem-solving in mathematics. Sal Khan video https://cdn.kastatic.org/googleusercontent/KG5lRGcQZUigp2H158bW1ijLQDdzKlMUxoIK0s5BVctNUDeMe-EdJYcFL0XOnhybPFmgYvTs2Ab5bv_zFc08cqI Terms, factors, & coefficients In math expressions, terms are the components added or subtracted, factors are the elements multiplied within each term, and coefficients are the numbers multiplying variables. Understanding these concepts is crucial for effective communication and problem-solving in mathematics. https://cdn.kastatic.org/ka-youtube-converted/9_VCk9tWT0Y.mp4/9_VCk9tWT0Y.mp4 441 Algebraic expressions https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:intro-variables/v/why-aren-t-we-using-the-multiplication-sign 2023-05-23T10:28:13.689545116Z Why aren't we using the multiplication sign? In algebra, representing multiplication with variables can be tricky due to the similarity between the variable "x" and the multiplication symbol. To avoid confusion, use alternative methods like 2⋅x, 2(x), or 2x. Practice evaluating expressions by substituting given values for variables and following the order of operations. Sal Khan video https://cdn.kastatic.org/googleusercontent/ktQxtEIS88xXcToePo4nuRJMGsrWlUaS9br45MuAwXBTu7v9IBQei-LLD-qTcmsKKL7X8KJ8ahrPC9ne2cgsdNPk Why aren't we using the multiplication sign? In algebra, representing multiplication with variables can be tricky due to the similarity between the variable "x" and the multiplication symbol. To avoid confusion, use alternative methods like 2⋅x, 2(x), or 2x. Practice evaluating expressions by substituting given values for variables and following the order of operations. https://cdn.kastatic.org/ka-youtube-converted/vDaIKB19TvY.mp4/vDaIKB19TvY.mp4 298 Algebraic expressions https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-evaluating-expressions/e/identifying-parts-of-expressions 2026-03-15T17:11:10.340789021Z Parts of algebraic expressions Practice identifying the following parts of algebraic expressions: sum, product, quotient, coefficient, factor, term, and variable.  allytobias exercise https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-evaluating-expressions/a/terms-factors-and-coefficients-review 2022-02-04T17:27:52.270593234Z Terms, factors, and coefficients review Review terms, factors, and coefficients, and try some practice problems.  article https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:intro-variables/v/variables-and-expressions-1 2023-06-11T20:09:24.00592199Z Evaluating an expression with one variable In this math lesson, we explore the expression 5 t plus 3 to calculate the cost of participating in a hospital raffle fundraiser. By evaluating the expression for different values of t, the number of tickets purchased, we find the costs for buying 1, 8, and 10 tickets, which are 8, 43, and 53 dollars, respectively. Sal Khan video https://cdn.kastatic.org/googleusercontent/uIAXUtdyJRfQMcSwOvbNBBbvYyFxGpIsznKE9aM5HHsUTWfdzOTNmL_BQHea9f9oD_NaMb5EtADwbhHP-x3Orao Evaluating an expression with one variable In this math lesson, we explore the expression 5 t plus 3 to calculate the cost of participating in a hospital raffle fundraiser. By evaluating the expression for different values of t, the number of tickets purchased, we find the costs for buying 1, 8, and 10 tickets, which are 8, 43, and 53 dollars, respectively. https://cdn.kastatic.org/ka-youtube-converted/AJNDeVt9UOo.mp4/AJNDeVt9UOo.mp4 120 Algebraic expressions https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:intro-variables/e/evaluating_expressions_1 2025-03-28T07:05:36.573142233Z Evaluating expressions with one variable Substitute a whole number into an expression with 1 or 2 operations (addition, subtraction, multiplication, and division), and evaluate. Marcia Lee exercise https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-substitution/v/evaluating-exponent-expressions-with-variables 2023-06-30T02:13:42.781179102Z Evaluating exponent expressions with variables In this math lesson, we learn to evaluate expressions with exponents and variables. We practice substituting values for variables and calculating the results. By mastering this skill, we can solve problems involving exponential expressions, enhancing our understanding of algebra and mathematical concepts. video https://cdn.kastatic.org/ka_thumbnails_cache/ed2fd4cf-265f-4470-94ce-dcb800aba937_1280_720_base.png Evaluating exponent expressions with variables In this math lesson, we learn to evaluate expressions with exponents and variables. We practice substituting values for variables and calculating the results. By mastering this skill, we can solve problems involving exponential expressions, enhancing our understanding of algebra and mathematical concepts. https://cdn.kastatic.org/ka-youtube-converted/9K54G5yeR74.mp4/9K54G5yeR74.mp4 181 Algebraic expressions https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-substitution/v/evaluating-expressions-5x2 2023-06-30T13:52:18.186404311Z Evaluating expressions like 5x² & ⅓(6)ˣ Evaluating expressions with exponents involves substituting a given value for the variable and following the order of operations. Calculate the exponent first, then perform any multiplication or division. Mastering this skill is essential for solving more complex algebraic problems and understanding mathematical relationships. Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/71ba61c7-d195-436a-a95e-abe0f8bfff6f_1280_720_base.png Evaluating expressions like 5x² & ⅓(6)ˣ Evaluating expressions with exponents involves substituting a given value for the variable and following the order of operations. Calculate the exponent first, then perform any multiplication or division. Mastering this skill is essential for solving more complex algebraic problems and understanding mathematical relationships. https://cdn.kastatic.org/ka-youtube-converted/ccyZpjKvJV8.mp4/ccyZpjKvJV8.mp4 86 Algebraic expressions https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-substitution/e/exponents-in-expressions 2022-07-28T09:36:48.454963052Z Variable expressions with exponents Practice evaluating expressions with exponents by substituting values for the variables.  Lindsay exercise https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:intro-variables/a/evaluating-expressions-with-one-variable 2026-06-12T17:50:45.743340147Z Evaluating expressions with one variable A mixture of explanations, examples, and practice problems to have you evaluating expressions with one variable in no time! article https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-writing-expressions/a/writing-basic-algebraic-expressions 2021-06-30T17:51:09Z Writing basic expressions with variables Learn to write expressions for phrases like "3 more than x." article https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:substitute-evaluate-expression/v/evaluating-expressions-in-two-variables 2023-05-23T10:28:13.689545116Z Evaluating expressions with two variables Evaluating expressions with multiple variables involves substituting given values for each variable and simplifying the expression. By replacing variables with their corresponding values, we can easily compute the result of expressions, even for more complex examples with multiple terms and operations. Sal Khan video https://cdn.kastatic.org/googleusercontent/iq0X7eHKRMR7hfRc9mv4FyGygVfST6BBHqCNP68H6jRMR_bZ7vvnI1IxdP9ixbNILdvxF4YpfpS7SiGx7vtfzQSx Evaluating expressions with two variables Evaluating expressions with multiple variables involves substituting given values for each variable and simplifying the expression. By replacing variables with their corresponding values, we can easily compute the result of expressions, even for more complex examples with multiple terms and operations. https://cdn.kastatic.org/ka-youtube-converted/S_OX3ByvBSc.mp4/S_OX3ByvBSc.mp4 125 Algebraic expressions https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:substitute-evaluate-expression/a/evaluating-expressions-with-two-variables 2021-06-30T17:51:08Z Evaluating expressions with two variables We've already evaluated expressions with one variable. Now it's time to do it with two variables. article https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:foundation-algebra/x2f8bb11595b61c86:substitute-evaluate-expression/e/evaluating_expressions_2 2026-04-02T16:00:53.810662107Z Evaluating expressions with multiple variables Practice evaluating expressions in two variables by plugging in values for the variables.  Omar Rizwan exercise https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-equations-and-inequalities/x0267d782:cc-6th-analyzing-relationships/v/equations-relationships-quantities 2023-06-30T13:52:18.186404311Z Writing equations for relationships between quantities In this lesson, we learn how to write equations representing real-world scenarios. First, we explore how to calculate time taken for a walk based on speed and distance. Then, we discover how to determine the amount of water needed in a soup recipe based on the quantity of vegetable stock. Fun, right? Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/d046ad3f-4af8-45c7-8aa0-442607603601_1280_720_base.png Writing equations for relationships between quantities In this lesson, we learn how to write equations representing real-world scenarios. First, we explore how to calculate time taken for a walk based on speed and distance. Then, we discover how to determine the amount of water needed in a soup recipe based on the quantity of vegetable stock. Fun, right? https://cdn.kastatic.org/ka-youtube-converted/5T9gSp2W3Oc.mp4/5T9gSp2W3Oc.mp4 361 Algebraic expressions https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-writing-expressions/a/writing-expressions-with-variables 2021-06-30T17:51:07Z Writing expressions with variables Learn to write expressions for more challenging phrases like "8 less than the product of 7 and x." article https://www.khanacademy.org/math/mappers/operations-and-algebraic-thinking-220-223/x261c2cc7:algebraic-equations-basics/e/identify-equations--expressions--and-inequalities 2026-04-08T01:15:04.085520103Z Identify equations, expressions, and inequalities Identify whether a math phrase is an equation, an expression, or an inequality. Lindsay exercise