8th grade · Math · Unit 2 of 11
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.
Minnesota K-12 Academic Standards benchmark: 8.3.6.3 · solving multi-step 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 Minnesota
In the Minnesota K-12 Academic Standards, this is unit 2 of 11 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.
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: 8x − 7 = 89
answer box
12
Hint: Undo the subtraction first: 8x = 89 + 7 = 96. Then divide by 8: x = 12.
Question 2
Solve for x: x ÷ 4 + 1 = 7
answer box
24
Hint: Subtract 1: x ÷ 4 = 6. Multiply both sides by 4: x = 24.
Question 3
Solve for n: 24 = 6n + 18
answer box
1
Hint: Subtract 18 from both sides: 6 = 6n. Divide by 6: n = 1.
Question 4
Evaluate 7n + 8 when n = 8.
answer box
64
Hint: Replace n with 8: 7 × 8 + 8 = 56 + 8 = 64.
Question 5
Which expression means “2 more than 2 times a number n”?
- 2n − 2
- 4n
- 2n + 2
- 2(n + 2)
2n + 2
Hint: “2 times a number” is 2n. “2 more than” that means add 2: 2n + 2.
Question 6
I think of a number, multiply it by 4 and add 4. The result is 12. Which equation matches?
- n + 16 = 12
- 4 + 4n = 12
- 4n + 4 = 12
- 4n − 4 = 12
- 4(n + 4) = 12
4n + 4 = 12
Hint: "Multiply by 4" gives 4n, then "add 4" gives 4n + 4, and that equals 12.