Introduction
The AMC 8 math contest challenges middle school students with tricky problems that go beyond school textbooks. Algebra alone makes up a big portion of the test—from simple arithmetic identities to sequences and word problems. Therefore, it is important to learn algebra formulas for AMC 8 during the preparation.
In this guide, we’ll walk through 7 must-know AMC 8 algebra formulas, each paired with a real AMC-8 problem, a quick solution, and a “why it matters” tip. By the end, you’ll have a compact AMC 8 algebra formula sheet that’s both practical and contest-ready.
1. Basic Operations (Distributive, Commutative, Associative)
Formulas:

Example (AMC 8 2017, Problem 8)

Why it matters: Long expressions collapse with grouping. Students who don’t see the pattern often waste time adding term by term.
2. Fractions and Ratios
Formulas:

Example (AMC 8 2020, Problem 15):

Why it matters: Percent word problems are common. The trick is setting up the correct ratio before calculating.
3. Exponents and Quadratics
Formulas:

Example (AMC 8 2019, Problem 20):

Why it matters: Substitution is a contest lifesaver. Missing the “±” is a classic mistake.
4. Radicals (Nested Roots)
Formula:

Example (AMC 8 2017, Problem 3):

Why it matters: Always work inside out. Skipping steps here almost always leads to mistakes.
5. Absolute Value
Formulas:

Example (AMC 8 2017, Problem 21):

Why it matters: Absolute value problems often reduce to sign-case logic.
6. Algebraic Operations (Special Products)
Formulas:

Example (AMC 8 2017, Problem 5):

Why it matters: These identities save time when expanding or collapsing large expressions.
7. Arithmetic Sequences
Formulas:

Example (AMC 8 2018, Problem 5):

Why it matters: Count terms carefully—miscounting is the #1 source of errors.
Wrap-Up: Turning Formulas into Points
These 7 sections cover nearly all the algebra you’ll face on AMC 8:
- Identities and operations
- Fractions and ratios
- Exponents and radicals
- Absolute value logic
- Sequences and special products
- Word problems (embedded throughout)
With formulas in hand and practice on real AMC 8 questions, students can solve quickly and confidently.
How Canadian Students Can Prepare
At Think Academy Canada, our AMC 8 programs guide students step by step:
- Build strong foundations (fractions, equations)
- Practice past AMC 8 algebra problems under timed conditions
- Transition smoothly to AMC 10 and Waterloo contests
If you are seeking for more real contest problems from AMC8, feel free to check this article: AMC 8 Real Questions 2025 Paper Analysis: Key Problems and How to Prepare
Book a Free Evaluation today to get started.