Cogito
Algebra 1 · Chapter 1 · Lesson 3
Distributing and Collecting
Two moves that do most of the work in algebra.
11 problems · about 22 minutes · A-SSE.A.1, A-APR.A.1
Figure — use these to answer the problems
7 + 7 + 7 = 21
3 × 7 = 21
3 × 7 = (3 × 4) + (3 × 3) = 12 + 9 = 21
Warm Up
Straightforward practice. Get the method working first.
4 problemsSimplify 3(x + 2) + 4x. How many x?
AnswerExpand 4(x + 2). Number term?
AnswerSimplify 3x + 5x. How many x?
AnswerExpand 6(x − 3). Number term?
Answer
Build It Up
The same ideas with more to keep track of.
3 problemsSimplify 2(x + 1) + 3x. How many x?
AnswerSelect every pair that can be combined into one term.
- 4x and 9x
- 4x and 9x²
- 6 and 11
- 6 and 11x
- Tick every box that applies.
Simplify 2(x + 1) + 3x. What is the number term?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsIs 3(x + 4) the same as 3x + 4? 1 for yes, 0 for no.
AnswerOrder the steps for simplifying 5(x + 2) + 3x.
Write 1 to 3 in the boxes to put these in order.
- Expand the bracket
- Collect the x terms
- Collect the plain numbers
The Bracket
Expand 5(x + 3). What is the number term?
AnswerCollecting
Simplify 7x + 2x. How many x?
Answer