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.
Maine Learning Results 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 Maine
In the Maine Learning Results, 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: Maine 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: 3x − 2 = 34
answer box
12
Hint: Undo the subtraction first: 3x = 34 + 2 = 36. Then divide by 3: x = 12.
Question 2
Solve for x: x ÷ 6 + 7 = 13
answer box
36
Hint: Subtract 7: x ÷ 6 = 6. Multiply both sides by 6: x = 36.
Question 3
Solve for n: 36 = 4n + 8
answer box
7
Hint: Subtract 8 from both sides: 28 = 4n. Divide by 4: n = 7.
Question 4
Evaluate 7n + 3 when n = 2.
answer box
17
Hint: Replace n with 2: 7 × 2 + 3 = 14 + 3 = 17.
Question 5
Which expression means “6 more than 3 times a number n”?
- 3(n + 6)
- 9n
- 3n − 6
- 6n + 3
- 3n + 6
3n + 6
Hint: “3 times a number” is 3n. “6 more than” that means add 6: 3n + 6.
Question 6
I think of a number, multiply it by 2 and add 14. The result is 20. Which equation matches?
- 2(n + 14) = 20
- 2n + 14 = 20
- 2 + 14n = 20
- n + 28 = 20
- 2n − 14 = 20
2n + 14 = 20
Hint: "Multiply by 2" gives 2n, then "add 14" gives 2n + 14, and that equals 20.