Please wait while we process your payment
If you don't see it, please check your spam folder. Sometimes it can end up there.
If you don't see it, please check your spam folder. Sometimes it can end up there.
Please wait while we process your payment
By signing up you agree to our terms and privacy policy.
Don’t have an account? Subscribe now
Create Your Account
Sign up for your FREE 7-day trial
By signing up you agree to our terms and privacy policy.
Already have an account? Log in
Your Email
Choose Your Plan
Individual
Group Discount
Save over 50% with a SparkNotes PLUS Annual Plan!
Purchasing SparkNotes PLUS for a group?
Get Annual Plans at a discount when you buy 2 or more!
Price
$24.99 $18.74 /subscription + tax
Subtotal $37.48 + tax
Save 25% on 2-49 accounts
Save 30% on 50-99 accounts
Want 100 or more? Contact us for a customized plan.
Your Plan
Payment Details
Payment Summary
SparkNotes Plus
You'll be billed after your free trial ends.
7-Day Free Trial
Not Applicable
Renews March 21, 2025 March 14, 2025
Discounts (applied to next billing)
DUE NOW
US $0.00
SNPLUSROCKS20 | 20% Discount
This is not a valid promo code.
Discount Code (one code per order)
SparkNotes PLUS Annual Plan - Group Discount
Qty: 00
SparkNotes Plus subscription is $4.99/month or $24.99/year as selected above. The free trial period is the first 7 days of your subscription. TO CANCEL YOUR SUBSCRIPTION AND AVOID BEING CHARGED, YOU MUST CANCEL BEFORE THE END OF THE FREE TRIAL PERIOD. You may cancel your subscription on your Subscription and Billing page or contact Customer Support at custserv@bn.com. Your subscription will continue automatically once the free trial period is over. Free trial is available to new customers only.
Choose Your Plan
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
For the next 7 days, you'll have access to awesome PLUS stuff like AP English test prep, No Fear Shakespeare translations and audio, a note-taking tool, personalized dashboard, & much more!
You’ve successfully purchased a group discount. Your group members can use the joining link below to redeem their group membership. You'll also receive an email with the link.
Members will be prompted to log in or create an account to redeem their group membership.
Thanks for creating a SparkNotes account! Continue to start your free trial.
We're sorry, we could not create your account. SparkNotes PLUS is not available in your country. See what countries we’re in.
There was an error creating your account. Please check your payment details and try again.
Please wait while we process your payment
Your PLUS subscription has expired
Please wait while we process your payment
Please wait while we process your payment
Introduction and Summary
As the final SparkNote within Pre-Algebra, this guide serves as the jumping off point from pre-algebra to algebra. As such, this chapter will introduce the reader to variables and how to evaluate expressions and solve equations that contain variables.
The first section will explain what a variable is and how variables are used. This is essential knowledge--variables are the crux of algebra.
The second section will deal with algebraic expressions--that is, expressions containing a variable. It will explain how to evaluate an algebraic expression, given a quantity for the variable.
The final section is an introduction to solving algebraic equations--equations that contain a variable. It will teach the reader how to determine which number a variable represents by using inverse operations. This topic will reappear in algebra; in fact, much of algebra is concerned with solving equations for variables.
The material covered in this section is very important. It is the gateway from pre-algebra to algebra. Much of this study guide has been concerned with understanding operations and how they can be applied to given numbers. Now, we will begin to explore operations on unknown numbers. This chapter will introduce the concept of representing unknown numbers by variables, which will be used in all of mathematics--algebra and beyond--as well as physics, chemistry, statistics, and economics.
Please wait while we process your payment