To evaluate an expression, you put a number where the letter is, then follow the order of operations. So this lesson runs on substituting a value into a blank and doing multiply/add in the right order. Warm those up first.
Answer these 3, then press Show my path. No grade — this just points you to the right level.
1. If the box ▢ = 4, what is ▢ + 3?
2. If ▢ = 5, what is 2 × ▢?
3. Which do you do first in 2 + 3 × 4?
To evaluate, replace the letter (or box) with its number, then do the math. When there is both × and +, do the multiply first.
Your quick check picks one for you, but you can switch any time:
Level 0 Drop the number into the box, one step at a time.
A. The box ▢ = 6. What is ▢? Just write the number.
The box holds 6, so it is 6.
B. ▢ = 6. What is ▢ + 2?
Put 6 in: 6 + 2 = 8.
C. ▢ = 6. What is ▢ − 4?
Put 6 in: 6 − 4 = 2.
Level 1 Substitute, then do the order of operations.
A. n = 5. What is n + 7?
5 + 7 = 12.
B. n = 3. What is 2 × n?
2 × 3 = 6.
C. n = 4. What is 2 × n + 1? (multiply first)
2 × 4 = 8, then 8 + 1 = 9.
Level 2 Warm up straight into evaluating.
A. x = 5. What is 3 × x − 2?
3 × 5 = 15, then 15 − 2 = 13.
B. x = 6. What is x ÷ 2 + 4?
6 ÷ 2 = 3, then 3 + 4 = 7.
1. n = 4. What is n + 6?
4 + 6 = 10.
2. n = 3. What is 2 × n + 5? (multiply first)
2 × 3 = 6, then 6 + 5 = 11.
You've practiced exactly what Lesson 6-2 uses. Time to dive in.
Start Lesson 6-2 →