Can we solve in two calm moves?
By the end of this lesson
Solve the three common two-step shapes (ax+b, ax−b, x/a + b) with one step per line and a check.
Remember
- Pattern A: ax + b = c → subtract b, divide by a.
- Pattern B: ax − b = c → add b, divide by a.
- Pattern C: x/a + b = c → subtract b, multiply by a.
- One step per line. Then check in the original.
- If the check fails, the slip is usually a sign or a divide.
Worked examples
Cover the answer. Try the steps on paper, then open them.
Example 1 — Pattern A
5x + 2 = 17
- −2 both sides: 5x = 15
- ÷5: x = 3
- Check: 5(3)+2 = 17 ✓
Answer: x = 3
Example 2 — Pattern B
4x − 7 = 9
- +7 both sides: 4x = 16
- ÷4: x = 4
- Check: 4(4)−7 = 9 ✓
Answer: x = 4
Example 3 — Pattern C
x/2 + 1 = 6
- −1 both sides: x/2 = 5
- ×2: x = 10
- Check: 10/2 + 1 = 6 ✓
Answer: x = 10
Example 4 — Pattern B again
3x − 5 = 10
- +5: 3x = 15
- ÷3: x = 5
- Check: 3(5)−5 = 10 ✓
Answer: x = 5
Common mistakes
Slip 5x + 2 = 17 → x = 17 − 2 − 5 = 10
Fix You must divide the 15 by 5, not subtract 5.
After −2 you have 5x = 15.
Slip 4x − 7 = 9 → subtract 7 again to get 4x = 2
Fix The −7 is undone by +7.
9 + 7 = 16.
Slip x/2 + 1 = 6 → multiply by 2 first and drop the +1
Fix Subtract 1 first: x/2 = 5, then ×2.
Outer layer first.
Try on paper first
Write the answer, then tap Reveal. These are not the quiz — they are warm-ups.
1. 6x + 1 = 19 → x =
Answer: 3
2. 2x − 9 = 7 → x =
Answer: 8
3. x/3 + 4 = 7 → x =
Answer: 9
4. 5x − 5 = 20 → x =
Answer: 5
Touch practice
9 tap / typeTap an option or type the answer. Retry any miss. Extra generated questions appear after the set if this topic allows it.
Optional picture lab
After practiceReal world
Pay a fee, then split the rest.
Connect
Two-step programs: subtract, then divide.
⭐ Star quiz
9 questionsFinish the touch practice first if you can. Then answer without peeking. Read every “why”.