Algebra and Graphs

Basic Expressions and Formulas

Introduction to Mapping

Introduction to Formulas

Deriving and Evaluating Expressions with One Variable

Equations and Simplifications

Simplifying Expressions

Solving Equations

Solving Rational Equations

Simplifying Expressions with Multiple Variables

Expanding and Binomials

Expanding Double Brackets

Square of a Binomial

Quadratic Equations

Simple Quadratic Equations

Vertex Form and Parabola Transformations

Converting Quadratics: Standard Form and Vertex Form

How to Write Quadratic Equations in Vertex Form and Standard Form

Solving Simple Quadratic Equations

Solving Quadratic Equations by Factorising

Solving Quadratic Equations: Quadratic Formula

Functions and Graphs

Plotting and Reflecting Points on the Coordinate Plane

Introduction to Functions and Graphs

Gradient and Y-Intercept in Linear Equations

Finding the Equation of a Straight Line

1 of 2

Previous Lesson

{results_count} Math videos for {phrase}

Displaying {results_count} results of {results_count_total}

Generic filters

Exact matches only

Search in title

Search in content

Search in excerpt

Filter by Lesson Categories

Deriving and Evaluating Expressions with One Variable

Algebra and Graphs Deriving and Evaluating Expressions with One Variable

Courses Overview

🎬 Video Tutorial

(0:01) What is a Variable? A variable in maths is a symbol, usually a letter like $x$ or $y$, that represents a number that can change. It is often used in algebra to write expressions and equations.
(1:00) Expressions with One Variable (Example): In $20+5x$, $x$ represents the number of months, and the expression calculates total savings after $x$ months. Creating variable expressions helps solve real-life problems easily.
(1:42) How to Evaluate Expressions with One Variable: Replace the variable with a given value to find the result. In expression $50 – 3y$, where $y$ represents the number of snack packs. If $y = 10$, the balance is $50 – (3 × 10) = 20$, meaning after buying 10 packs, £20 remains.

📂 Revision Cards

An example of expressions with one variable 20 + 5x, where the variable x represents the number of months. — 1) Expressions with One Variable (Example)

Algebraic expression showing balance calculation using the variable y for the number of packs of chips costing £3 each. — 2) How to Evaluate Expression with One Varaible

🍪 Quiz Time - Practice Now!

0%

Expressions with One Variable

1 / 6

Q: Julia has £20 in savings. Each month, she saves an additional £5. How much will she have saved after 5 months?

45

40

30

35

Feedback: Not quite! The expression is $20 + 5x$. After 5 months, Julia will have 20 + 5 × 5 = 45 (£).

Feedback: Well done! The expression is $20 + 5x$. After 5 months, Julia will have 20 + 5 × 5 = 45 (£).

2 / 6

Q: A library has 200 books. Every week, 10 new books are added. How many books will the library have after 3 weeks?

240

220

250

230

Feedback: Not quite! The expression is $200 + 10x$. After 3 weeks, the library will have 200 + 10 × 3 = 230 books.

Feedback: Well done! The expression is $200 + 10x$. After 3 weeks, the library will have 200 + 10 × 3 = 230 books.

3 / 6

Q: You start with £100, and you spend £8 each day. How much money will you have left after 12 days?

8

16

4

12

Feedback: Not quite! The expression is $100 - 8x$. After 12 days, you'll have 100 - 8 × 12 = 100 - 96 = 4 (£) left.

Feedback: Well done! The expression is $100 - 8x$. After 12 days, you'll have 100 - 8 × 12 = 100 - 96 = 4 (£) left.

4 / 6

Q: A factory starts with 1000 units of a product. They produce 125 units every day. After how many days will they have a total of 2000 units?

10

12

8

6

Feedback: Not quite! The equation is $1000 + 125x = 2000$. Solving for $x$, we get $x = \frac{2000 - 1000}{125} = 8$ days.

Feedback: Well done! The equation is $1000 + 125x = 2000$. Solving for $x$, we get $x = \frac{2000 - 1000}{125} = 8$ days.

5 / 6

Q: A gardener plants 15 flowers each day. They start with 50 flowers already planted. How many flowers will they have after 7 days?

140

145

160

155

Feedback: Not quite! The expression is $50 + 15x$. After 7 days, the gardener will have 50 + 15 × 7 = 50 + 105 = 155 flowers in total.

Feedback: Well done! The expression is $50 + 15x$. After 7 days, the gardener will have 50 + 15 × 7 = 50 + 105 = 155 flowers in total.

6 / 6

Q: A photographer charges £50 for a session. They charge an additional £30 for each extra photo. How much will the photographer charge after 12 photos?

390

370

380

410

Feedback: Not quite! The expression is $50 + 30 \times (x - 1)$. After 12 photos, x = 12, the photographer will charge: 50 + 30 × (12 – 1) = 50 + 30 × 11 = 50 + 330 = 380 (£).

Feedback: Well done! The expression is $50 + 30 \times (x - 1)$. After 12 photos, x = 12, the photographer will charge: 50 + 30 × (12 – 1) = 50 + 30 × 11 = 50 + 330 = 380 (£).

Your score is

The average score is 39%

0%

🎩 AI Math Solver (ChatCat)

Need math help? Chat with our AI Math Solver at the bottom right!

Previous Lesson

0 0 votes

Article Rating

Label

Name*

Email

Label

Name*

Email

0 Comments

Newest

Oldest Most Voted

Inline Feedbacks

View all comments

Leave a Comment Cancel reply

Your email address will not be published. Required fields are marked *

Comment *

Name

Email

Website

Save my name, email, and website in this browser for the next time I comment.

Log In

Username or Email Address

Password

Remember Me

Join Now | Lost Password?

Login

Accessing this course requires a login. Please enter your credentials below!

Username or Email Address

Password

Remember Me

Lost Your Password?

Register

Don't have an account? Register one!

Register an Account