Cogito
Algebra 1 · Chapter 1 · Lesson 1
Expressions and Their Structure
Reading an expression before touching it.
8 problems · about 18 minutes · A-SSE.A.1, A-SSE.A.2
What this lesson teaches
The student identifies terms, coefficients, and factors, and uses the properties of operations to rewrite expressions.
- Terms are separated by plus and minus signs.
- Only like terms combine.
- Distributing multiplies everything inside the bracket.
Warm Up
Straightforward practice. Get the method working first.
4 problems3(4x − 2) expands to 12x − what?
Answer 6
Why 12x − 6.
What makes two terms like terms?
Answer The same variable to the same power.
Why Same variable, same power.
5(2x + 3) expands to 10x + what?
Answer 15
Why 5 × 3.
9x − 2x simplifies to how many x?
Answer 7
Why 9 − 2.
Build It Up
The same ideas with more to keep track of.
2 problemsIn 4x² − 7x + 2, what is the coefficient of x?
Answer -7
Why Include the sign.
Can 3x and 3x² be combined?
Answer No. Different powers.
Why Like terms need the same power.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
2 problemsCombining: 7x + 4x simplifies to how many x?
Answer 11
Why 11x.
Distributing: 6(x + 4) expands to 6x + what?
Answer 24
Why 6x + 24.