8th grade · Math · Unit 2 of 17
Patterns & Two-Step Equations
Expressions, patterns and solving for x
What your child practices
Writing and evaluating expressions like 3n + 2, solving two-step equations, and finding the rule for a growing pattern or a cost made of whole items such as tickets.
Arizona Academic Standards learning standard: 8.EE.C.7 · solving linear equations in one variable
How we explain it
Children can open this short lesson before they practice.
- Do the same thing to both sides to keep the equation balanced.
- Undo adding and subtracting first.
- Then undo multiplying and dividing.
Example: 3x − 5 = 16 Add 5 to both sides: 3x = 21. Divide both sides by 3: x = 7. Answer: x = 7
Patterns & Two-Step Equations in Arizona
In the Arizona Academic Standards, this is unit 2 of 17 in 8th grade Math, after Squares, Cubes & Roots and before Pythagorean Theorem.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Arizona Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Solve for x: 2x + 5 = 3
answer box
-1
Hint: Undo the addition first: 2x = 3 − 5 = -2. Then divide by 2: x = -1.
Question 2
Solve for x: x ÷ 6 + 9 = 15
answer box
36
Hint: Subtract 9: x ÷ 6 = 6. Multiply both sides by 6: x = 36.
Question 3
Solve for n: 60 = 4n + 20
answer box
10
Hint: Subtract 20 from both sides: 40 = 4n. Divide by 4: n = 10.
Question 4
Evaluate 6n + 8 when n = 6.
answer box
44
Hint: Replace n with 6: 6 × 6 + 8 = 36 + 8 = 44.
Question 5
Which expression means “5 more than 4 times a number n”?
- 5n + 4
- 9n
- 4(n + 5)
- 4n − 5
- 4n + 5
4n + 5
Hint: “4 times a number” is 4n. “5 more than” that means add 5: 4n + 5.
Question 6
I think of a number, multiply it by 4 and add 9. The result is 29. Which equation matches?
- 4n − 9 = 29
- 4n + 9 = 29
- 4 + 9n = 29
- n + 36 = 29
- 4(n + 9) = 29
4n + 9 = 29
Hint: "Multiply by 4" gives 4n, then "add 9" gives 4n + 9, and that equals 29.